hal: Fix device disable/enable sequence

  In Skype call, observed no rx data when headset is inserted
  during call.

  During device switch from handset to headset, audio HAL is
  enabling the headset mixer controls first then disabling
  handset mixer controls leading to no audio during downlink
  as codec clock in 8916 is disabled due to the followed
  sequence.

  The current device switch logic doesn't make sure that all
  previous devices are disabled before enabling the selected
  devices. Fix this by changing the logic to disable all the
  previous devices first and enable the selected devices.

  CRs-Fixed: 648710

Change-Id: I0adfb62ea0ad8e2a2fe1a5473732e8bef61c492a