kc1: Clear reboot mode garbage on cold reset

Reboot mode garbage is found on cold reset and might be seen as valid on the
next warm reset, thus it has to be cleared on cold reset.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>

board/amazon/kc1/kc1.c

@@ -110,6 +110,9 @@ int misc_init_r(void)
 
 		omap_reboot_mode_clear();
 	} else {
+		/* Reboot mode garbage may still be valid, so clear it. */
+		omap_reboot_mode_clear();
+
 		/*
 		 * When not rebooting, valid power on reasons are either the
 		 * power button, charger plug or USB plug.