RDMA/rxe: Remove dangling declaration of rxe_cq_disable()

rxe_cq_disable() has been removed but not its declaration.

Fixes: 78b26a33 ("RDMA/rxe: Remove tasklet call from rxe_cq.c")
Link: https://lore.kernel.org/r/4f20ffc5-b2c4-0c11-2883-a835caf01a94@suse.com


Signed-off-by: Nicolas Morey <nmorey@suse.com>
Acked-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>