net/mlx4_core: Fix uninitialized variable compilation warning

Initialize the uid variable to zero to avoid the compilation warning.

Fixes: 7a89399f ("net/mlx4: Add mlx4_bitmap zone allocator")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/alloc.c

@@ -337,7 +337,7 @@ void mlx4_zone_allocator_destroy(struct mlx4_zone_allocator *zone_alloc)
 static u32 __mlx4_alloc_from_zone(struct mlx4_zone_entry *zone, int count,
 				  int align, u32 skip_mask, u32 *puid)
 {
-	u32 uid;
+	u32 uid = 0;
 	u32 res;
 	struct mlx4_zone_allocator *zone_alloc = zone->allocator;
 	struct mlx4_zone_entry *curr_node;