[NFC][CVP] Count all the no-wraps we proved

Summary:
It looks like this is the only missing statistic in the CVP pass.
Since we prove NSW and NUW separately i'd think we should count them separately too.

Reviewers: nikic, spatel, reames

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68740

llvm-svn: 375230