SystemMonitor: Unveil /usr/local/lib

This is necessary to symbolicate libraries installed under
/usr/local/lib.

Userland/Applications/SystemMonitor/main.cpp

@@ -141,6 +141,11 @@ int main(int argc, char** argv)
         return 1;
     }
 
+    if (unveil("/usr/local/lib", "r") < 0 && errno != ENOENT) {
+        perror("unveil");
+        return 1;
+    }
+
     if (unveil("/bin/Profiler", "rx") < 0) {
         perror("unveil");
         return 1;