Fix GCC 12 compilation errors

Squelch false positives reported by GCC 12 with UBSan.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: szubersk <szuberskidamian@gmail.com>
Closes #14150

cmd/zfs/zfs_main.c

@@ -548,7 +548,7 @@ usage(boolean_t requested)
 		show_properties = B_TRUE;
 
 	if (show_properties) {
-		(void) fprintf(fp,
+		(void) fprintf(fp, "%s",
 		    gettext("\nThe following properties are supported:\n"));
 
 		(void) fprintf(fp, "\n\t%-14s %s  %s   %s\n\n",

cmd/zpool/zpool_main.c

@@ -548,7 +548,7 @@ usage(boolean_t requested)
 	    (strcmp(current_command->name, "get") == 0) ||
 	    (strcmp(current_command->name, "list") == 0))) {
 
-		(void) fprintf(fp,
+		(void) fprintf(fp, "%s",
 		    gettext("\nthe following properties are supported:\n"));
 
 		(void) fprintf(fp, "\n\t%-19s  %s   %s\n\n",