lib/libpayload: Replace strapping_ids with new board configuration entry

There are currently 3 different strapping ID entries in the coreboot
table, which adds overhead. The new fw_config field is also desired in
the coreboot table, which is another kind of strapping id. Therefore,
this patch deprecates the 3 current strapping ID entries (board ID, RAM
code, and SKU ID), and adds a new entry ("board_config") which provides
board ID, RAM code, SKU ID, as well as FW_CONFIG together.

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I1ecec847ee77b72233587c1ad7f124e2027470bf
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46605
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/include/fw_config.h

@@ -8,6 +8,8 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+#define UNDEFINED_FW_CONFIG	~((uint64_t)0)
+
 /**
  * struct fw_config - Firmware configuration field and option.
  * @field_name: Name of the field that this option belongs to.
@@ -30,8 +32,6 @@ struct fw_config {
 	.value = FW_CONFIG_FIELD_##__field##_OPTION_##__option##_VALUE		\
 })
 
-#if CONFIG(FW_CONFIG)
-
 /**
  * fw_config_get() - Provide firmware configuration value.
  *
@@ -39,6 +39,8 @@ struct fw_config {
  */
 uint64_t fw_config_get(void);
 
+#if CONFIG(FW_CONFIG)
+
 /**
  * fw_config_probe() - Check if field and option matches.
  * @match: Structure containing field and option to probe.