soc/amd/sabrina: Rename PSP SPL default

Change the SPL file from the 'cezanne' placeholder to a mendocino
filename.  Also, move the default location to blobs/mainboard since
it's not board-agnostic.

BUG=b:241543152
BUILD=Enable feature and build amd/chausie

Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Change-Id: I47647c5d926484e25e3f893e72c671554e277a56
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66465
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>
diff --git a/src/soc/amd/sabrina/Kconfig b/src/soc/amd/sabrina/Kconfig
index 4b14b6c..14ae5b0 100644
--- a/src/soc/amd/sabrina/Kconfig
+++ b/src/soc/amd/sabrina/Kconfig
@@ -416,7 +416,7 @@
 config SPL_TABLE_FILE
 	string "SPL table file"
 	depends on HAVE_SPL_FILE
-	default "3rdparty/amd_blobs/cezanne/PSP/TypeId0x55_SplTableBl_CZN.sbin"
+	default "3rdparty/blobs/mainboard/\$(CONFIG_MAINBOARD_DIR)/TypeId0x55_SplTableBl_MDN.sbin"
 
 config PSP_SOFTFUSE_BITS
 	string "PSP Soft Fuse bits to enable"