console: Revise serial console configuration names.

The console drivers (especially serial drivers) in Kconfig were named in
different styles. This change will rename configuration names to a better naming
style.

 - EARLY_CONSOLE:
        Enable output in pre-ram stage. (Renamed from EARLY_SERIAL_CONSOLE
        because it also supports non-serial)

 - CONSOLE_SERIAL:
        Enable serial output console, from one of the serial drivers. (Renamed
        from SERIAL_CONSOLE because other non-serial drivers are named as
        CONSOLE_XXX like CONSOLE_CBMEM)

 - CONSOLE_SERIAL_UART:
	Device-specific UART driver. (Renamed from
	CONSOLE_SERIAL_NONSTANDARD_MEM because it may be not memory-mapped)

 - HAVE_UART_SPECIAL:
        A dependency for CONSOLE_SERIAL_UART.

Verified to boot on x86/qemu and armv7/snow, and still seeing console
messages in romstage for both platforms.

Change-Id: I4bea3c8fea05bbb7d78df6bc22f82414ac66f973
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2299
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>

src/arch/armv7/lib/romstage_console.c

@@ -20,7 +20,7 @@
 #include <console/console.h>
 #include <console/vtxprintf.h>
 // TODO Unify with x86 (CONFIG_CONSOLE_SERIAL8250)
-#if CONFIG_SERIAL_CONSOLE
+#if CONFIG_CONSOLE_SERIAL
 #include <uart.h>
 #endif
 #if CONFIG_USBDEBUG
@@ -33,7 +33,7 @@ void console_tx_byte(unsigned char byte)
 	if (byte == '\n')
 		console_tx_byte('\r');
 
-#if CONFIG_SERIAL_CONSOLE
+#if CONFIG_CONSOLE_SERIAL_UART
 	uart_tx_byte(byte);
 #endif
 #if CONFIG_USBDEBUG
@@ -46,7 +46,7 @@ void console_tx_byte(unsigned char byte)
 
 static void _console_tx_flush(void)
 {
-#if CONFIG_SERIAL_CONSOLE
+#if CONFIG_CONSOLE_SERIAL_UART
 	uart_tx_flush();
 #endif
 #if CONFIG_USBDEBUG