DO NOT MERGE ANYWHERE hal: Implement Tx mute in ASM loopback am: 666786ddcb  -s ours am: 1ac36f79aa  -s ours am: f10797ba87  -s ours am: 28aece0ed6  -s ours
am: 9acf3c7106  -s ours

Change-Id: I4c4c3da018849970f1af5c98b4e14c3a4ffbb607