u_gralloc: Add a function that returns gralloc type

This is needed by some drivers to reject the fallback gralloc.

Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25256>

src/util/u_gralloc/u_gralloc.c

@@ -58,6 +58,7 @@ u_gralloc_create(enum u_gralloc_type type)
          assert(u_gralloc_cache[type].u_gralloc->ops.get_buffer_basic_info);
          assert(u_gralloc_cache[type].u_gralloc->ops.destroy);
 
+         u_gralloc_cache[type].u_gralloc->type = u_grallocs[i].type;
          u_gralloc_cache[type].refcount = 1;
 
          out_gralloc = u_gralloc_cache[type].u_gralloc;
@@ -148,3 +149,9 @@ u_gralloc_get_front_rendering_usage(struct u_gralloc *gralloc,
 
    return gralloc->ops.get_front_rendering_usage(gralloc, out_usage);
 }
+
+int
+u_gralloc_get_type(struct u_gralloc *gralloc)
+{
+   return gralloc->type;
+}