libstdc++: Fix more pedwarns in headers for C++98

libstdc++: Fix more pedwarns in headers for C++98

Some tests e.g.  17_intro/headers/c++1998/all_pedantic_errors.cc FAIL
with GLIBCXX_TESTSUITE_STDS=98 due to numerous C++11 extensions still in
use in the library headers. The recent changes to not make them system
headers means we get warnings now.

This change adds more diagnostic pragmas to suppress those warnings.

libstdc++-v3/ChangeLog:

	* include/bits/istream.tcc: Add diagnostic pragmas around uses
	of long long and extern template.
	* include/bits/locale_facets.h: Likewise.
	* include/bits/locale_facets.tcc: Likewise.
	* include/bits/locale_facets_nonio.tcc: Likewise.
	* include/bits/ostream.tcc: Likewise.
	* include/bits/stl_algobase.h: Likewise.
	* include/c_global/cstdlib: Likewise.
	* include/ext/pb_ds/detail/resize_policy/hash_prime_size_policy_imp.hpp:
	Likewise.
	* include/ext/pointer.h: Likewise.
	* include/ext/stdio_sync_filebuf.h: Likewise.
	* include/std/istream: Likewise.
	* include/std/ostream: Likewise.
	* include/tr1/cmath: Likewise.
	* include/tr1/type_traits: Likewise.
	* include/tr1/functional_hash.h: Likewise. Remove semi-colons
	at namespace scope that aren't needed after macro expansion.
	* include/tr1/tuple: Remove semi-colon at namespace scope.
	* include/bits/vector.tcc: Change LL suffix to just L.