Finish "core" renaming to avoid prefs crashes

Close #10096
swscale: handle 4:2:0 and 4:2:2 YUVA formats
avcodec: handle codecs outputting YUVA 4:2:0 and 4:2:2
flac: move CRC update into STATE_NEXT_SYNC

Fixes #9966.
ogg: fix format strings for debug messages
v4l2: set visible height
access/alsa.c: fix racecondition on demux->p_sys variable

The Thread() function could access demux->p_sys before it was assigned a value other then NULL.
If this happens then it will crash on line 158 while accessing sys->pcm.
Revert "flac: fix extradata clamping check"

This reverts commit 16e9999966c12f696de57b0e7e5c0f39d7b0f621.

We use short flac extra format if it does *not* start with the header.
Thus we need not to add ! in front of memcmp
Merge remote-tracking branch: upstream/master