Don't inline @llvm.icall.branch.funnel

Summary: @llvm.icall.branch.funnel is musttail with variable number of
arguments. After inlining current backend can't separate call targets from call
arguments.

Reviewers: pcc

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45116

llvm-svn: 329235