V4L/DVB (10109): anysee: Fix usage of an unitialized function

drivers/media/dvb/dvb-usb/anysee.c: In function ‘anysee_master_xfer’:
drivers/media/dvb/dvb-usb/anysee.c:156: warning: ‘ret’ may be used uninitialized

By looking at the function, altrough very unlikely, this might
eventually be true if num  = 0. So, better to fix the warning by
initializing with ret = 0.

Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>