msm: ipa3: remove ipa q6 pipe emptiness check

Removing ipa q6 pipes emptiness check when
getting post_shutdown from SSR framework
to make adb reboot to work. The full
SSR support will be done later.

CRs-fixed: 2216929
Change-Id: I433b3a4413fd4659735739694ae3382edf8ed2e6
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>