msm: camera: reqmgr: Allow requests to be submitted in IDLE state

Allow requests to be submitted by UMD and added by devices on
the link, irrespective of the link state.

CRs-Fixed: 2718108
Change-Id: Ie6a6f3576bc6aeb1657ee751dc72779cafec7ffe
Signed-off-by: Karthik Anantha Ram <kartanan@codeaurora.org>