Fix build failure revealed by c35ca3a1

This commit resolves a Linux kernel build failure that was revealed by
c35ca3a1. The patch introduces two new
intrinsics, which ultimately changes the intrinsic numbering of other PPC
intrinsics. This causes an issue introduced by
ff40fb07, as the patch checks for intrinsics
with particular values, but the addition of the fnabs/fnabss intrinsics updates
the original sqrt/sdiv intrinsic values.