mb/google/nissa/var/telith: Add Fn key scancode

The Fn key on telith emits a scancode of 94 (0x5e).

BUG=b:372506691
TEST=Flash telith, boot to Linux kernel, and verify that KEY_FN is
generated when pressed using `evtest`.

Change-Id: Ib69af9a8448312b275de46f9c835f8a9d592312a
Signed-off-by: Kun Liu <liukun11@huaqin.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85045
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/mainboard/google/brya/Kconfig

@@ -562,6 +562,7 @@ config BOARD_GOOGLE_TELITH
 	select DRIVERS_GENERIC_GPIO_KEYS
 	select DRIVERS_GFX_GENERIC
 	select DRIVERS_INTEL_MIPI_CAMERA
+	select MAINBOARD_HAS_GOOGLE_STRAUSS_KEYBOARD
 	select SOC_INTEL_TWINLAKE
 
 config BOARD_GOOGLE_TEREID