RDMA/mlx5: Fix UMR modifying of mkey page size

RDMA/mlx5: Fix UMR modifying of mkey page size

When changing the page size on an mkey, the driver needs to set the
appropriate bits in the mkey mask to indicate which fields are being
modified.
The 6th bit of a page size in mlx5 driver is considered an extension,
and this bit has a dedicated capability and mask bits.

Previously, the driver was not setting this mask in the mkey mask when
performing page size changes, regardless of its hardware support,
potentially leading to an incorrect page size updates.

This fixes the issue by setting the relevant bit in the mkey mask when
performing page size changes on an mkey and the 6th bit of this field is
supported by the hardware.

Fixes: cef7dde8836a ("net/mlx5: Expand mkey page size to support 6 bits")
Signed-off-by: Edward Srouji <edwards@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/9f43a9c73bf2db6085a99dc836f7137e76579f09.1751979184.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>