remove "OMX.SEC.aac.dec" from media_codecs.xml to fix YouTube issues

googles version will be used instead.
Thanks @Vincent Hamon for finding the fix.

Change-Id: I7ced04f9538da727de95ae2ef189403bd298f59a
Merge pull request #5 from omnirom/android-4.4

remove "OMX.SEC.aac.dec" from media_codecs.xml to fix YouTube issues