dri2: Fix memory leak.

Fix defect reported by Coverity Scan.

Resource leak (RESOURCE_LEAK)
leaked_storage: Variable psp going out of scope leaks the storage it points to.

Fixes: 68aa2099fa ("dri2: Require a loader with working buffer invalidation")
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16680>

src/gallium/frontends/dri/dri_util.c

@@ -122,8 +122,10 @@ driCreateNewScreen2(int scrn, int fd,
 
     setupLoaderExtensions(psp, extensions);
     // dri2 drivers require working invalidate
-    if (fd != -1 && !psp->dri2.useInvalidate)
+    if (fd != -1 && !psp->dri2.useInvalidate) {
+       free(psp);
        return NULL;
+    }
 
     psp->loaderPrivate = data;