m7-common: libaudioamp: split amp functionality into amp files

Change-Id: Idd5c0e73a4d49b6f8ba227bd1de2e33f92500960
m7-common: tfa9887: initial implementation of tfa9887 amp control

Change-Id: Ie51c5a27409c76b9394a85ce1dc9cfe18679a996
Merge "m7-common: libaudioamp: split amp functionality into amp files" into cm-10.2
Merge "m7-common: tfa9887: initial implementation of tfa9887 amp control" into cm-10.2