default aac-profile to low instead of main

If someone understands the stochastic process whereby GCC decides to
apply this function or not, please let me know.

vout_intf: do not vlc_object_release() the cache object since it no more obtained through vlc_object_find

Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

Signed-off-by: Rémi Denis-Courmont <rdenis@simphalempin.com>

sacred knowledge shouldnt be forgotten by future generations of VLC
devs.

It it locked when returning from vlc_object_wait/vlc_cond_wait

Conflicts:

	src/input/decoder.c

This reverts commit 3c9681e1.
It breaks DMO/Qt decoding. It can be commited again when a fix
is found.