Under situations where the driver detects wifi capabilities are not
being used, it cleans itself up transparently to the kernel and shuts
down. The kernel has been observed calling the stop AP callback in
these situations, even though no virtual devices are active, which
causes a crash. Gracefully reject the calls into stop AP by the
kernel in such cases.
Change-Id: Ic215b033526125412ebe12c0021c61b20f4c86a1
CRs-Fixed: 2001200
6807c74d09