media: cx25840: Address several coding style issues

As we did a major change on this file, let's take the moment
to cleanup several coding style issues on it.

This patch was partially done with the help of two tools:

	./scripts/checkpatch.pl --fix-inplace --strict
	astyle --indent=tab=8 --style=linux

But manually adjusted in order to fit our style.

Signed-off-by: Mauro Carvalho Chehab <[email protected]>