media: cxusb: use dev_dbg() rather than hand-rolled debug

media: cxusb: use dev_dbg() rather than hand-rolled debug

This solves the following compiler warnings:

drivers/media/usb/dvb-usb/cxusb.c: In function ‘cxusb_gpio_tuner’:
drivers/media/usb/dvb-usb/cxusb.c:128:35: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
  128 |   deb_info("gpio_write failed.\n");
      |                                   ^
drivers/media/usb/dvb-usb/cxusb.c: In function ‘cxusb_bluebird_gpio_rw’:
drivers/media/usb/dvb-usb/cxusb.c:145:44: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
  145 |   deb_info("bluebird_gpio_write failed.\n");
      |                                            ^
drivers/media/usb/dvb-usb/cxusb.c: In function ‘cxusb_i2c_xfer’:
drivers/media/usb/dvb-usb/cxusb.c:251:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
  251 |     deb_i2c("i2c read may have failed\n");
      |                                          ^
drivers/media/usb/dvb-usb/cxusb.c:274:43: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
  274 |     deb_i2c("i2c write may have failed\n");
      |                                           ^

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>