Make sure that the type of the loop index matches the type of the upper bound. This fixes several -Wsign-compare warnings. Change-Id: I73a88355d86288609e03f7a6fcaec14dfedac203 Signed-off-by: Jacob Garber <jgarber1@ualberta.ca> Reviewed-on: https://review.coreboot.org/c/coreboot/+/33863 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>