mb/asus/maximus_iv_gene-z: Add VBT

The file `data.vbt` matches the VBT in the latest version of the vendor
firmware (version 3603). Tested with Linux 4.9 and everything works as
expected.

Change-Id: I8e3b1d274ac0df63989d966f477013e780611fa1
Signed-off-by: Tristan Corrick <tristan@corrick.kiwi>
Reviewed-on: https://review.coreboot.org/28050
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/asus/maximus_iv_gene-z/Kconfig

@@ -24,6 +24,7 @@ config BOARD_SPECIFIC_OPTIONS
 	select HAVE_ACPI_TABLES
 	select HAVE_OPTION_TABLE
 	select HAVE_CMOS_DEFAULT
+	select INTEL_GMA_HAVE_VBT
 	select INTEL_INT15
 	select MAINBOARD_HAS_LIBGFXINIT
 	select NORTHBRIDGE_INTEL_SANDYBRIDGE