RDMA/mlx5: Fix ucaps init error flow

RDMA/mlx5: Fix ucaps init error flow

In mlx5_ib_stage_caps_init(), if mlx5_ib_init_ucaps() fails after
mlx5_ib_init_var_table() succeeds, the VAR bitmap is leaked since
the function returns without cleanup.

Thus, cleanup the var table bitmap in case of error of initializing
ucaps before exiting, preventing the leak above.

Fixes: cf7174e8982f ("RDMA/mlx5: Create UCAP char devices for supported device capabilities")
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://patch.msgid.link/20260104-ib-core-misc-v1-3-00367f77f3a8@nvidia.com
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>