XQuartz: Silence a clang static analysis warning about a possible memory leak on exit

stub.c:356:9: warning: Potential leak of memory pointed to by 'newargv'
        asl_log(aslc, NULL, ASL_LEVEL_ERR,
        ^~~~~~~
stub.c:356:9: warning: Potential leak of memory pointed to by 'newenvp'
        asl_log(aslc, NULL, ASL_LEVEL_ERR,
        ^~~~~~~
2 warnings generated.

Signed-off-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>

hw/xquartz/mach-startup/stub.c

@@ -353,6 +353,10 @@ main(int argc, char **argv, char **envp)
     newenvp = (string_array_t)calloc((1 + envpc), sizeof(string_t));
 
     if (!newargv || !newenvp) {
+        /* Silence the clang static analyzer */
+        free(newargv);
+        free(newenvp);
+
         asl_log(aslc, NULL, ASL_LEVEL_ERR,
                 "Xquartz: Memory allocation failure");
         return EXIT_FAILURE;