Use official ffmpeg 4.4.2 with Matrix
Doing so SEEMS TO avoid sporatic A/V sync issues with concomitant lines in the log like:
ActiveAE - large audio sync error: -89515.453679
ActiveAE - large audio sync error: -89515.536515
CVideoReferenceClock: detected 1 vblanks, missed 2, refreshrate might have changed
Also fixes broken HW accel decoding on more recent kernels, see: https://github.com/raspberrypi/linux/issues/5136
Removed the following parameters:
1. selinux=0
2. plymouth.enable=0
3. smsc95xx.turbo_mode=N
4. dwc_otg.lpm_enable=0
5. kgdboc=serial0,115200
Notes:
1. force not loading SELinux infrastructure which we currently do not supply
2. force disabling of plymouth which I think we do not supply
3. avoided network issues under heavy load circa 2012 likely no longer needed
4. turned off link power management which may have prevented issues with shitty
drivers in older kernels likely not an issue on a modern kernel tree
5. enabled debugging over the serial console which is unnecessary for most
user... advanced users will likely be savvy enough with cmdline.txt to
edit it to match their needs
New package is required for HW decoding with vlc-rpi. Use -mcpu in C/XXFLAGS
which will limit use of this package to RPi3 and above which isn't a big
loss since HW decoding on RPi2 is pretty limited. Commit also makes this
a split package with the new ffmpeg-rpi-bin providing the man pages and
executables stripped out in the main package to allow a full package of
ffmpeg with HW decoding should someone what that.