KVM: selftests: Make reclaim_period_ms input always be positive

reclaim_period_ms used to be positive only but the commit 0001725
("KVM: selftests: Add atoi_positive() and atoi_non_negative() for input
validation") incorrectly changed it to non-negative validation.

Change validation to allow only positive input.

Fixes: 0001725 ("KVM: selftests: Add atoi_positive() and atoi_non_negative() for input validation")
Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reported-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230111183408.104491-1-vipinsh@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c

@@ -241,7 +241,7 @@ int main(int argc, char **argv)
 	while ((opt = getopt(argc, argv, "hp:t:r")) != -1) {
 		switch (opt) {
 		case 'p':
-			reclaim_period_ms = atoi_non_negative("Reclaim period", optarg);
+			reclaim_period_ms = atoi_positive("Reclaim period", optarg);
 			break;
 		case 't':
 			token = atoi_paranoid(optarg);