cnss2: Request runtime PM resume when shutdown happens

Request runtime PM resume in platform driver as soon as shutdown
happens. This can make sure device is resumed while shutdown is
proceeding.

Change-Id: I0aa15b9713347288f4954bd767ec9243d22153ed
CRs-fixed: 2124999
Signed-off-by: Yue Ma <yuem@codeaurora.org>