Remove TLI from isInTailCallPosition's arguments. NFC.

There is no need to pass on TLI separately to the function. As Eric pointed out
the Target Machine already provides everything we need.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213108 91177308-0d34-0410-b5e6-96231b3b80d8