soc/intel/meteorlake: Apply large cbmem buffer size for FSP debug

This patch ensures that the PRERAM_CBMEM_CONSOLE_SIZE and
CONSOLE_CBMEM_BUFFER_SIZE hold a larger cbmem buffer size to contain
the entire FSP debug serial log.

The existing implementation was not appropriate, where the larger cbmem
size was even applicable for serial AP firmware (w/o FSP debug) image
as well.

This change is necessary to ensure that the FSP debug serial log is
always available, even in cases where the cbmem buffer size is
limited.

BUG=b:280481298
TEST=Able to build and boot google/rex with non-FSP serial AP image
and with FSP serial AP image. Able to see the AP log completely inside
the cbmem.

Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: Ib35780fd558c8b6d9aa2e17241131ea4a58c2b9c
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75030
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/soc/intel/meteorlake/Kconfig b/src/soc/intel/meteorlake/Kconfig
index 7762d5f..ee29b50 100644
--- a/src/soc/intel/meteorlake/Kconfig
+++ b/src/soc/intel/meteorlake/Kconfig
@@ -301,12 +301,12 @@
 
 config PRERAM_CBMEM_CONSOLE_SIZE
 	hex
-	default 0x16000 if CONSOLE_SERIAL
+	default 0x16000 if BUILDING_WITH_DEBUG_FSP
 	default 0x2000
 
 config CONSOLE_CBMEM_BUFFER_SIZE
 	hex
-	default 0x100000 if CONSOLE_SERIAL
+	default 0x100000 if BUILDING_WITH_DEBUG_FSP
 	default 0x40000
 
 config FSP_HEADER_PATH