chromeos: Clean up elog handling

1. Currenty, boot reason is being added to elog only for some
ARM32/ARM64 platforms. Change this so that boot reason is logged by
default in elog for all devices which have CHROMEOS selected.

2. Add a new option to select ELOG_WATCHDOG_RESET for the devices that
want to add details about watchdog reset in elog. This requires a
special region WATCHDOG to be present in the memlayout.

3. Remove calls to elog add boot reason and watchdog reset from
mainboards.

BUG=chrome-os-partner:55639

Change-Id: I91ff5b158cfd2a0749e7fefc498d8659f7e6aa91
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/15897
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)

src/mainboard/google/gru/mainboard.c

@@ -189,9 +189,6 @@ static void mainboard_init(device_t dev)
 	register_reset_to_bl31();
 	register_poweroff_to_bl31();
 	setup_rtc();
-
-	elog_init();
-	elog_add_boot_reason();
 }
 
 static void enable_backlight_booster(void)

src/mainboard/google/nyan/mainboard.c

@@ -242,10 +242,6 @@ static void mainboard_init(device_t dev)
 	setup_kernel_info();
 	clock_init_arm_generic_timer();
 	setup_ec_spi();
-#if CONFIG_ELOG
-	elog_init();
-	elog_add_boot_reason();
-#endif
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/nyan_big/mainboard.c

@@ -240,10 +240,6 @@ static void mainboard_init(device_t dev)
 	setup_kernel_info();
 	clock_init_arm_generic_timer();
 	setup_ec_spi();
-#if CONFIG_ELOG
-	elog_init();
-	elog_add_boot_reason();
-#endif
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/nyan_blaze/mainboard.c

@@ -240,10 +240,6 @@ static void mainboard_init(device_t dev)
 	setup_kernel_info();
 	clock_init_arm_generic_timer();
 	setup_ec_spi();
-#if CONFIG_ELOG
-	elog_init();
-	elog_add_boot_reason();
-#endif
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/oak/mainboard.c

@@ -267,10 +267,6 @@ static void mainboard_init(device_t dev)
 	configure_usb_hub();
 	configure_ext_buck();
 	configure_touchscreen();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/rush_ryu/mainboard.c

@@ -269,9 +269,6 @@ static void mainboard_init(device_t dev)
 	/* Temp hack for P1 board: Enable speaker amp (powerup, etc.) */
 	enable_ad4567_spkr_amp();
 
-	elog_init();
-	elog_add_boot_reason();
-
 	fix_ec_sw_sync();
 
 	/* configure panel gpio pads */

src/mainboard/google/veyron/mainboard.c

@@ -108,10 +108,6 @@ static void mainboard_init(device_t dev)
 	configure_emmc();
 	configure_codec();
 	configure_vop();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/veyron_brain/mainboard.c

@@ -93,10 +93,6 @@ static void mainboard_init(device_t dev)
 	configure_codec();
 	configure_vop();
 	configure_hdmi();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/veyron_danger/mainboard.c

@@ -149,10 +149,6 @@ static void mainboard_init(device_t dev)
 	configure_codec();
 	configure_vop();
 	configure_hdmi();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/veyron_emile/mainboard.c

@@ -111,10 +111,6 @@ static void mainboard_init(device_t dev)
 	configure_i2s();
 	configure_vop();
 	configure_hdmi();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/veyron_mickey/mainboard.c

@@ -87,10 +87,6 @@ static void mainboard_init(device_t dev)
 	configure_i2s();
 	configure_vop();
 	configure_hdmi();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)

src/mainboard/google/veyron_rialto/mainboard.c

@@ -85,10 +85,6 @@ static void mainboard_init(device_t dev)
 	configure_3g();
 	/* No video. */
 
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
-
 	/* If recovery mode is detected, reduce frequency and voltage to reduce
 	 * heat in case machine is left unattended. chrome-os-partner:41201. */
 	if (vboot_recovery_mode_enabled())  {

src/mainboard/google/veyron_romy/mainboard.c

@@ -86,10 +86,6 @@ static void mainboard_init(device_t dev)
 	configure_emmc();
 	configure_codec();
 	configure_vop();
-
-	elog_init();
-	elog_add_watchdog_reset();
-	elog_add_boot_reason();
 }
 
 static void mainboard_enable(device_t dev)