mb/google/hatch: set Tianocore boot timeout to 5s for PUFF-based boards

PUFF-based Chromeboxes need more than the 2s default in order to init
an external display and show the boot splash/menu prompt.

Test: build/boot WYVERN variant, ensure boot splash/menu prompt visible
regardless of display init type used.

Change-Id: Ie6d2151d28058501498a4c501bb221919b4e1b39
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48979
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>

src/mainboard/google/hatch/Kconfig

@@ -188,4 +188,8 @@ config VBOOT
 config USE_PM_ACPI_TIMER
 	default n
 
+config TIANOCORE_BOOT_TIMEOUT
+	int
+	default 5 if BOARD_GOOGLE_BASEBOARD_PUFF
+
 endif # BOARD_GOOGLE_HATCH_COMMON