sdma end ts must be 256 bit aligned in oss 3.0 and prior. Using
the ts pool requires copying into the signal and is a significant
performance penalty for small copies.
SharedSignal is 128 bytes due to alignment so can host the end ts.
Move sdma end ts into SharedSignal and remove ts pool and ts copy.
Change-Id: I7899bda36ebc9adcaad1d3a3d2b7a489857cc9e8
Sean Keely
ec5ac95dce