[CodeGen] translate MS rotate builtins to LLVM funnel-shift intrinsics

This was originally part of:
D50924

and should resolve PR37387:
https://bugs.llvm.org/show_bug.cgi?id=37387

...but it was reverted because some bots using a gcc host compiler 
would crash for unknown reasons with this included in the patch. 
Trying again now to see if that's still a problem.

llvm-svn: 347527