cnss2: Reject idle restart if fails to get driver ops lock

Reject idle restart request if it fails to acquire driver ops lock to
avoid deadlock inside WLAN driver. E.g. Driver remove from unregister
driver request will be blocked if idle restart request is pending.

Change-Id: I5825e02961117eaaea4202812a5d2d7140799e19
Signed-off-by: Yue Ma <yuem@codeaurora.org>