Coding standards: don't use ``inline`` when defining a function in a class

Coding standards: don't use ``inline`` when defining a function in a class
definition

Current practice is not to use 'inline' in:

  class Foo {
  public:
    inline void bar() {
      // ...
    }
  };

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174317 91177308-0d34-0410-b5e6-96231b3b80d8