mb/google/mancomb: Enable DISABLE_SPI_FLASH_ROM_SHARING

BUG=b:182211161
TEST=builds

Signed-off-by: Eric Lai <ericr_lai@compal.corp-partner.google.com>
Change-Id: I1d28c2335b095a77285dcb261a0dffe96d129c46
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52125
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
diff --git a/src/mainboard/google/mancomb/Kconfig b/src/mainboard/google/mancomb/Kconfig
index 6a9692c..b681a1e 100644
--- a/src/mainboard/google/mancomb/Kconfig
+++ b/src/mainboard/google/mancomb/Kconfig
@@ -9,6 +9,7 @@
 	def_bool y
 	select AMD_SOC_CONSOLE_UART
 	select BOARD_ROMSIZE_KB_16384
+	select DISABLE_SPI_FLASH_ROM_SHARING
 	select EC_GOOGLE_CHROMEEC
 	select EC_GOOGLE_CHROMEEC_BOARDID
 	select EC_GOOGLE_CHROMEEC_ESPI