rpmsg: glink: mark intent request complete before wake up

Channel release function is not making intent wait condition true
before calling wake_up, due to this thread waiting on intent is
stuck and does not wake up until timeout happens. By this time
channel context is freed and this casues finish wait to fail due
to access of wait queue in freed channel context.

Mark intent request complete before calling wake_up.

CRs-Fixed: 2914979
Change-Id: Ia4162c9e62f0f5a7bd04ca0e09c2cd58319ef341
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>