ksmbd: fix kernel oops in ksmbd_rpc_ioctl/rap()

"ksmbd: remove macros in transport_ipc.c" commit change msg to req in
ksmbd_rpc_ioctl/rap(). This will cause kernel oops when running smbclient
-L test.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>