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

This fixes some const qualifier violation in modules.

This was a bit too early.

This reverts commit b827afa2.

Conflicts:

	configure.ac

This reverts commit 66341140 and correctly undefine out: if needed.

Reported by Hugo Beauzée-Luyssen.

Warnings that are 'safe' to be treated as error should be added here as well.

I hope this will raise VLC code quality, and tend to lower the hudge number of warnings. Some of them are sometimes letal but hidden by others.