C2 Vts: Remove unused C2AllocatorIon.h dependency

Bug: 185952409
Test: atest VtsHalMediaC2V1_0TargetAudioDecTest \
 VtsHalMediaC2V1_0TargetAudioEncTest \
 VtsHalMediaC2V1_0TargetVideoDecTest \
 VtsHalMediaC2V1_0TargetVideoEncTest
Change-Id: I24a1ff10bae7955fd67393370451b5faf8aa0398
4 files changed