configure: fix help for macosx-bundle from autodetected to disabled

The help and configure result wrongly showed this feature was autodetected,
while it is infact disabled by default.
gl_video: fix odd video sizes with PBOs

Odd video sizes if pixel formats with chroma subsampling and PBOs were
used, garbage was rendered. This was because the PBO path created
buffers with an unpadded size, and then tried to upload a padded
image to it. Fix it by explicitly setting the padded size. (As with
the non-PBO path, we rely that image allocations are somehow padded,
which is normally the case.)
cocoa_common: autohide dock when autohiding menubar

A cocoa bug doesn't allow to do otherwise. Will open a radar later.
gl_video: don't crash if no FBOs are available

This probably has been broken since bbc865a: a test was added that uses
a FBO, but it's always run, even if FBOs were not detected. On the other
hand, fbotex_init() just runs into an assert. Fix the test that
triggered this condition, and make fbotex_init() "nicer" by just failing
if FBOs are not available.
input: fix --no-input-default-bindings

The option did nothing. This was probably broken with 5b38a52.