Fix build errors

 - include <sys/uio.h> in order to resolve use of undeclared identifier
 'writev'
  - implement abstract methods for QC value-adds on BaseWifiService
  - update files to match in specs in api/current.txt and api/system-current.txt
  - media/jni/Android.bp needed a static dependency moved to shared
  object dependency

Bug: 123699636
Change-Id: I30f97e24e83274016e720548fba412da0f35c98f