media: cec: tda9950: add back i2c dependency

drivers/media/cec/i2c/tda9950.c: In function 'tda9950_write_range':
drivers/media/cec/i2c/tda9950.c:92:15: error: implicit declaration of function 'i2c_transfer' [-Wimplicit-function-declaration]
   92 |         ret = i2c_transfer(client->adapter, &msg, 1);
      |               ^~~~~~~~~~~~
drivers/media/cec/i2c/tda9950.c: In function 'tda9950_probe':
drivers/media/cec/i2c/tda9950.c:391:14: error: implicit declaration of function 'i2c_check_functionality' [-Wimplicit-function-declaration]
  391 |         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
      |              ^~~~~~~~~~~~~~~~~~~~~~~

Fixes: caa6f4a7 ("media: cec: move driver for TDA9950 from drm/i2c")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>