mb/google/zork: meet SAR depedencies

DRIVERS_WIFI_GENERIC is a dependency for these SAR settings.
However, coreboot.org builders are not failing, but chromium
builders are only for serial configurations. It's not clear as
to why. Either way correct this.

BUG=b:159304570

Change-Id: I978b622a3a5a2490b0e3aaa14c24807d5afdff9a
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44825
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/zork/Kconfig

@@ -260,6 +260,7 @@ config EFS_SPI_MICRON_FLAG
 config CHROMEOS_WIFI_SAR
 	bool
 	default y if CHROMEOS
+	select DRIVERS_WIFI_GENERIC
 	select DSAR_ENABLE
 	select SAR_ENABLE
 	select USE_SAR