[inliner]: Refactor inline deferring logic into its own method /NFC

The implemented heuristic has a large body of code which better sits
in its own function for better readability. It also allows adding more
heuristics easier in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268107 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed