[SystemZ] Fix wrong codegen caused by typos in vecintrin.h

The following two bugs in SystemZ high-level vector intrinsics are
fixes by this patch:

- The float case of vec_insert_and_zero should generate a VLLEZF
  pattern, but currently erroneously generates VLLEZLF.

- The float and double versions of vec_orc erroneously generate
  and-with-complement instead of or-with-complement.

The patch also fixes a couple of typos in the associated test.

llvm-svn: 349751