staging: ks7010: Remove trailing _t from 'struct pmk_cache_t'.

The "_t" suffix is not needed for structure names in this driver, and is a
reflection of an older typedef system that is no longer in place. Replace
all occurences of 'struct pmk_cache_t' with 'struct pmk_cache'.

Signed-off-by: Quytelda Kahja <quytelda@tamalin.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>