RDMA/rxe: Move rxe_xmit_packet to a subroutine

rxe_xmit_packet() was an overlong inline subroutine. This patch moves it
into rxe_net.c as an ordinary subroutine.

Link: https://lore.kernel.org/r/20210707040040.15434-3-rpearsonhpe@gmail.com


Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Reviewed-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>