mb/purism/librem_skl: adjust CBFS_SIZE

Adjust default CBFS_SIZE to match that used in configs for building

Change-Id: Ibe1312560a923dcdefb8af52a721ab76c0b08a2e
Signed-off-by: Matt DeVillier <matt.devillier@puri.sm>
Reviewed-on: https://review.coreboot.org/c/31008
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/mainboard/purism/librem_skl/Kconfig b/src/mainboard/purism/librem_skl/Kconfig
index 224779d..0c138a6 100644
--- a/src/mainboard/purism/librem_skl/Kconfig
+++ b/src/mainboard/purism/librem_skl/Kconfig
@@ -77,6 +77,6 @@
 
 config CBFS_SIZE
 	hex
-	default 0x5c0000
+	default 0xe00000
 
 endif