V4L/DVB: AZ6027: Fix build warnings

drivers/media/dvb/dvb-usb/az6027.c:390: warning: excess elements in struct initializer
drivers/media/dvb/dvb-usb/az6027.c:390: warning: (near initialization for ‘az6027_rc_keys[0]’)
drivers/media/dvb/dvb-usb/az6027.c:391: warning: excess elements in struct initializer
drivers/media/dvb/dvb-usb/az6027.c:391: warning: (near initialization for ‘az6027_rc_keys[1]’)
drivers/media/dvb/dvb-usb/az6027.c:759: warning: ‘az6027_read_mac_addr’ defined but not used

Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>