RDMA/mana_ib: use the correct page size for mapping user-mode doorbell page

RDMA/mana_ib: use the correct page size for mapping user-mode doorbell page

When mapping doorbell page from user-mode, the driver should use the system
page size as this memory is allocated via mmap() from user-mode.

Cc: stable@vger.kernel.org
Fixes: 0266a177631d ("RDMA/mana_ib: Add a driver for Microsoft Azure Network Adapter")
Signed-off-by: Long Li <longli@microsoft.com>
Link: https://patch.msgid.link/1725030993-16213-2-git-send-email-longli@linuxonhyperv.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>