Subzero: Don't bother printing stack/frame ptr as part of LiveIn/LiveOut.

Subzero: Don't bother printing stack/frame ptr as part of LiveIn/LiveOut.

The LiveIn and LiveOut register sets are printed for each basic block in -asm-verbose mode.  These sets would generally include the stack and/or frame pointer registers, which is just noise, so we suppress that.

BUG= none
R=jpp@chromium.org

Review URL: https://codereview.chromium.org/1399523003 .