net: ipc_router: Decrement ref count for remote port

Ref count for remote port pointer is not being decremented
at function exit thereby causing memory leak of 128 byte.

Decrementing ref count for remote port pointer after its usage is done.

CRs-Fixed: 2315498
Change-Id: Ida00220201f3dba589a65d9b2ba84b83d6b00004
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>