icnss2: Do not start recovery timer on gracefull shutdown

Recovery timer is used to detect FW_READY timeout during
SSR/PDR recovery and assert when expires. In case of
gracefull shutdown avoid starting recovery timer.

Change-Id: Ieae2ae1d52db6648c1639ff5fca8fa9f004a6d7f
Signed-off-by: Naman Padhiar <quic_npadhiar@quicinc.com>