BugLink: https://bugs.launchpad.net/bugs/1811077

[ Upstream commit 3ea7e7ea ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>