RDMA/core: Avoid exporting module local functions and remove not-used ones

RDMA/core: Avoid exporting module local functions and remove not-used ones

Some of the functions are local to the module and some are not used
starting from commit 36783dec8d79 ("RDMA/rxe: Delete deprecated module
parameters interface"). Delete and avoid exporting them.

Signed-off-by: Parav Pandit <parav@nvidia.com>
Link: https://patch.msgid.link/20260104-ib-core-misc-v1-2-00367f77f3a8@nvidia.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>