mb/purism/librem_skl: select GFX_GMA_IGNORE_PRESENCE_STRAPS

Some Librem 13v4's don't have the presence straps connected,
leading libgfxinit to fail to init the internal display.
Select GFX_GMA_IGNORE_PRESENCE_STRAPS since all SKL/KBL Librems
have an internal display so there's no adverse effect.

Signed-off-by: Matt DeVillier <matt.devillier@puri.sm>
Change-Id: Ib9d281b7d495c4f9a5c6fc5fdb8042b0fcbda745
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41417
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/purism/librem_skl/Kconfig b/src/mainboard/purism/librem_skl/Kconfig
index 9760a2f..c86ebf1 100644
--- a/src/mainboard/purism/librem_skl/Kconfig
+++ b/src/mainboard/purism/librem_skl/Kconfig
@@ -2,6 +2,7 @@
 	def_bool n
 	select BOARD_ROMSIZE_KB_16384
 	select DRIVERS_GENERIC_CBFS_SERIAL
+	select GFX_GMA_IGNORE_PRESENCE_STRAPS
 	select HAVE_ACPI_RESUME
 	select HAVE_ACPI_TABLES
 	select INTEL_GMA_HAVE_VBT