Introduce M_LOG2E_F and M_LOG2E

Patch by: Jeroen Ketema

git-svn-id: https://llvm.org/svn/llvm-project/libclc/trunk@205055 91177308-0d34-0410-b5e6-96231b3b80d8
Remove clc/gentype.inc

This file duplicates clc/math/gentype.inc and is not
actually being used.

Patch by: Jeroen Ketema

git-svn-id: https://llvm.org/svn/llvm-project/libclc/trunk@207684 91177308-0d34-0410-b5e6-96231b3b80d8
Fix build broken by LLVM commit r207593

git-svn-id: https://llvm.org/svn/llvm-project/libclc/trunk@207685 91177308-0d34-0410-b5e6-96231b3b80d8