epca.c: reformat comments and coding style improvements

* Remove stupid comments, like, at the beginning of every function that
  function begins (twice per function) and at the end (once)
* Remove trailing or otherwise broken whitespace as per let c_space_errors=1
* Reformat comments to fit it into 80 columns and remove stupid ------------'s.
* Indent case labels on the same column where switch begins
* other minor CS tweaks not worth mentioning
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>