mb/google/mancomb: Add stubs to configure GPIOs

BUG=b:182211161
TEST=builds

Signed-off-by: Eric Lai <ericr_lai@compal.corp-partner.google.com>
Change-Id: I7de5e4a4d2273d0ea5a84210ea0ce28d312eaa95
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51365
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Mathew King <mathewk@chromium.org>

src/mainboard/google/mancomb/bootblock.c

@@ -5,5 +5,8 @@
 
 void bootblock_mainboard_early_init(void)
 {
-	/* TODO: Perform mainboard initialization */
+	size_t num_gpios;
+	const struct soc_amd_gpio *gpios;
+	gpios = variant_bootblock_gpio_table(&num_gpios);
+	program_gpios(gpios, num_gpios);
 }