soc/mediatek/mt8192: Initialize watch dog in bootblock

Initialize watch dog so the system won't reboot on timeout.
In addition, print the reason of reboot triggered by watch dog.

Signed-off-by: CK Hu <ck.hu@mediatek.com>
Change-Id: I7e849659700218f1c50365c2d68a32be2f703d94
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44434
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>

src/soc/mediatek/mt8192/bootblock.c

@@ -2,8 +2,10 @@
 
 #include <bootblock_common.h>
 #include <soc/mmu_operations.h>
+#include <soc/wdt.h>
 
 void bootblock_soc_init(void)
 {
 	mtk_mmu_init();
+	mtk_wdt_init();
 }