wl12xx: prevent sched_scan when not idle or not in station mode
wl12xx: prevent sched_scan when not idle or not in station mode

The current firmware only supports scheduled scan in station mode and
when idle.  To prevent the firmware from crashing, return -EOPNOTSUPP
when sched_scan start is called in an invalid state.

Signed-off-by: Luciano Coelho <d1ef580865f8eb2e1d1c65bc406aba322cc98f3e@ti.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs