Subzero, MIPS32: Intrinsic calls for ABS.fmt and SQRT.fmt

This patch adds ABS.fmt and SQRT.fmt instructions for intrinsic
calls. Test cases are copied from nacl-other-intrinsics.ll.

R=stichnot@chromium.org

Review URL: https://codereview.chromium.org/2325703002 .

Patch from Srdjan Obucina <Srdjan.Obucina@imgtec.com>.