Remove unnecessary "inline" of inline defined member functions

Member functions defined within a class definition are implicitly
'inline' for linkage purposes. Compilers might slightly favor inlining
functions explicitly marked 'inline', but LLVM doesn't make a stylistic
habit of doing this generally.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205679 91177308-0d34-0410-b5e6-96231b3b80d8