nb/i945/Kconfig: select the correct VGA_BIOS_ID for 945GC

Change-Id: I48ae27c5460020b9118e6ade1a3e610b542999c7
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/17040
Tested-by: build bot (Jenkins)
Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
diff --git a/src/northbridge/intel/i945/Kconfig b/src/northbridge/intel/i945/Kconfig
index 6e8d35b..e68a01a 100644
--- a/src/northbridge/intel/i945/Kconfig
+++ b/src/northbridge/intel/i945/Kconfig
@@ -38,7 +38,8 @@
 
 config VGA_BIOS_ID
 	string
-	default "8086,27a2"
+	default "8086,27a2" if NORTHBRIDGE_INTEL_SUBTYPE_I945GM
+	default "8086,2772" if NORTHBRIDGE_INTEL_SUBTYPE_I945GC
 
 config CHANNEL_XOR_RANDOMIZATION
 	bool