Apply the same approach of SSE4.1 ptest intrinsics but
create a new x86 node "testp" since AVX introduces
vtest{ps}{pd} instructions which set ZF and CF depending
on sign bit AND and ANDN of packed floating-point sources.

This is slightly different from what the "ptest" does.
Tests comming with the other 256 intrinsics tests.

llvm-svn: 110744