msm: pil-q6v5-lpass: Fix wcnss subsystem restart handling

Lpass handles wcnss subsystem restart incorrectly as it
does not receive SSR events for following two reasons:

1. Incorrect wcnss susbsystem name string passed during wcnss
SSR notifier registration call.

2. Sending only BEFORE_SHUTDOWN SSR event from wcnss.

Therefore, to fix the issue replace wcnss subsystem name string
in wcnss SSR notifier registration call from "riva" to "wcnss".
Remove filter on sending wcnss SSR event notifications to lpass.

CRs-fixed: 454916
Change-Id: I5df296178da64ccf0bc20df2b755d49a0e5626cf
Signed-off-by: Ravishankar Sarawadi <crsaraw@codeaurora.org>