This is done by auditing all callers of ucma_get_ctx and switching the
ones that unconditionally touch ->device to ucma_get_ctx_dev. This covers
a little less than  half of the call sites.

The 11 remaining call sites to ucma_get_ctx() were manually audited.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>