util/sconfig: Remove unnecessary strdup() calls

getopt() optarg value can be used without duplicaing if it is not
modified, as it is the case here.

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: Ie5a27f64077af1c04b06732cd601145b8becacfd
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70525
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

util/sconfig/main.c

@@ -1971,25 +1971,25 @@ int main(int argc, char **argv)
 				  &option_index)) != EOF) {
 		switch (opt) {
 		case 'm':
-			base_devtree = strdup(optarg);
+			base_devtree = optarg;
 			break;
 		case 'o':
-			override_devtree = strdup(optarg);
+			override_devtree = optarg;
 			break;
 		case 'p':
-			chipset_devtree = strdup(optarg);
+			chipset_devtree = optarg;
 			break;
 		case 'c':
-			outputc = strdup(optarg);
+			outputc = optarg;
 			break;
 		case 'r':
-			outputh = strdup(optarg);
+			outputh = optarg;
 			break;
 		case 'd':
-			outputd = strdup(optarg);
+			outputd = optarg;
 			break;
 		case 'f':
-			outputf = strdup(optarg);
+			outputf = optarg;
 			break;
 		case 'h':
 		default: