* include/c/bits/std_cwctype.h: #undef possible function-like

	* include/c/bits/std_cwctype.h: #undef possible function-like
	macro definitions of iswxxx functions, which might be brought in
	by <wctype.h>.  Those macro definitions prevent build on some
	linux-based systems.

	* include/bits/std_complex.h (complex<>): Comment out friend
	declarations of abs<> specializations.
	(abs): Define primary template.

	* src/complex.cc (abs): Comment out specialization definition.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@37157 138bc75d-0d04-0410-961f-82ee72b054a4