[media] pt3: fix DTV FE I2C driver load error paths

Get rid of 'module_is_live' usage.

on x86_64:
when CONFIG_MODULES is not enabled:

../drivers/media/pci/pt3/pt3.c: In function 'pt3_attach_fe':
../drivers/media/pci/pt3/pt3.c:433:6: error: implicit declaration of function 'module_is_live' [-Werror=implicit-function-declaration]

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Akihiro Tsukada <tskd08@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>