wcnss: fix enable wcnss bite IRQ warning

Bite IRQ is disabled when it's handler is called; and it is re-enabled
in SSR power-up. So if SSR was triggered by SMSM bit, then trying to
re-enable bite IRQ throws a warning. So move disable bite IRQ to SSR
shutdown routine.

Change-Id: Ib1434c6f0f389787fd3bb0dc1f4bf084a17081c4
CRs-Fixed: 346144
Signed-off-by: Sameer Thalappil <sameert@codeaurora.org>