icnss2: Use correct pointer to access icnss_priv state

Server arrive may come before initializing penv which
causes possible NULL pointer dereference.

To address this, use function argument priv instead of
global variable penv.

Change-Id: I1355074614b4f30fff1c021db53654b4c844135c
Signed-off-by: Dundi Raviteja <dundi@codeaurora.org>