staging: wilc1000: fix line over 80 charas in wilc_wfi_remain_on_channel_expired()

Refactor wilc_wfi_remain_on_channel_expired() to avoid line over 80
character issue reported by checkpatch.pl script. Also assigned value in the
variable at the time of declaration.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>