Extend tautological pointer compare and pointer to bool conversion warnings to

Extend tautological pointer compare and pointer to bool conversion warnings to
macro arguments.

Previously, these warnings skipped any code in a macro expansion.  Preform an
additional check and warn when the expression and context locations are both
in the macro argument.

The most obvious case not caught is passing a pointer directly to a macro,
i.e 'assert(&array)' but 'assert(&array && "valid array")' is caught.  This is
because macro arguments are not typed and the conversion happens inside the
macro.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215251 91177308-0d34-0410-b5e6-96231b3b80d8