access/file: don't read-ahead when processing remote contents (closes #9885, refs #8446)

OS X Mavericks takes read-ahead very seriously when accessing SMB drives, so it caches up to a 100 MB. However, when the end of said cache is reached, VLC will stutter because the file system needs to re-connect to the server first. Disabling read-ahead leads to a continous data flow at the media's bitrate.

This solves a regression introduced in fe0a075ef3
quartztext: remove write-only variables and a potential error-case leak
audiounit: cast OSStatus correctly for debug output
Contribs: update libass to 0.11.2
avcodec: Extend the check for impossible dimensions

Overly large frame sizes are commonly caused by broken streams.

Close #11245

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>