clear out C(), _i, and _f constants from SkJumper_vectors.h

clear out C(), _i, and _f constants from SkJumper_vectors.h

I think this is just gonna be a bunch of baby steps for now.
This gets everything in SkJumper_vectors.h.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Win7-MSVC-Golo-CPU-AVX-x86_64-Release,Test-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Release,Test-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Release-SK_CPU_LIMIT_SSE41,Test-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Release-SK_CPU_LIMIT_SSE2

Change-Id: Ic87faa9bf6380a4fc9a577936dad8c3a9c48472e
Reviewed-on: https://skia-review.googlesource.com/14441
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Herb Derby <herb@google.com>