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/cpu/intel/hyperthreading/intel_sibling.c

@@ -21,7 +21,7 @@ void intel_sibling_init(struct device *cpu)
 	/* On the bootstrap processor see if I want sibling cpus enabled */
 	if (first_time) {
 		first_time = 0;
-		disable_siblings = get_int_option("hyper_threading", disable_siblings);
+		disable_siblings = get_uint_option("hyper_threading", disable_siblings);
 	}
 	result = cpuid(1);
 	/* Is hyperthreading supported */