src: Retype option API to use unsigned integers

The CMOS option system does not support negative integers. Thus, retype
and rename the option API functions to reflect this.

Change-Id: Id3480e5cfc0ec90674def7ef0919e0b7ac5b19b3
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52672
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by:  Felix Singer <felixsinger@posteo.net>

src/console/init.c

@@ -26,7 +26,7 @@ static void init_log_level(void)
 	console_loglevel = get_console_loglevel();
 
 	if (!FIRST_CONSOLE)
-		console_loglevel = get_int_option("debug_level", console_loglevel);
+		console_loglevel = get_uint_option("debug_level", console_loglevel);
 }
 
 int console_log_level(int msg_level)