net/mlx4: Check retval of mlx4_bitmap_init

If mlx4_bitmap_init fails, mlx4_bitmap_alloc_range will dereference
the NULL pointer (bitmap->table).

Make sure, that mlx4_bitmap_alloc_range called in no error case.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: d57febe1 ("net/mlx4: Add A0 hybrid steering")
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Peter Kosyh <pkosyh@yandex.ru>
Link: https://lore.kernel.org/r/20221117152806.278072-1-pkosyh@yandex.ruSigned-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -697,7 +697,8 @@ static int mlx4_create_zones(struct mlx4_dev *dev,
 			err = mlx4_bitmap_init(*bitmap + k, 1,
 					       MLX4_QP_TABLE_RAW_ETH_SIZE - 1, 0,
 					       0);
-			mlx4_bitmap_alloc_range(*bitmap + k, 1, 1, 0);
+			if (!err)
+				mlx4_bitmap_alloc_range(*bitmap + k, 1, 1, 0);
 		}
 
 		if (err)