RDMA/core: Remove indirection through ib_cache_setup()

This once might have made sense when cache.c was in a different module
from device.c, but  today it just obfuscation. Get rid of the wrappers
and call roge_gid_mgmt_init()/cleanup() directly.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>