Use ALLOC_XMIT_OPCODE in ApfV61Generator

This commit refactors the ApfV61Generator to utilize the
ALLOC_XMIT_OPCODE for buffer allocation.

Before:
03-20 20:58:57.975 17833 17847 I ApfFilterTest: all feature on, program size: 4648

After:
03-20 21:14:08.987 18721 18735 I ApfFilterTest: all feature on, program size: 4597

Test: TH
Change-Id: I80ab159280f7ae79f3feb14c4e81d9633ee50a22
3 files changed