Merge commit 'f2c469b7'

* commit 'f2c469b7':
  mjpeg: Report non-3 component rgb lossless as not supported

[15:56:27] <jamrial> michaelni: can't reproduce the failure f2c469b7 is trying to "fix"
[15:56:30] <jamrial> do we support what that commit claims is unsupported?
[16:56:54] <michaelni> jamrial, yes, we support lossless rgba

This commit is a noop.
Merged-by: James Almer <jamrial@gmail.com>