Include throughout files using LoadLibrary function.
* cygcheck.cc (dump_sysinfo): Retrieve kernel32.dll handle via
GetModuleHandle, rather than using LoadLibrary.
* cygpath.cc (get_long_name): Ditto.
(do_sysfolders): Append .dll suffix in LoadLibrary call.
* ldh.cc (WinMain): Use LoadLibraryExW with DONT_RESOLVE_DLL_REFERENCES
to avoid loading malicious library code.
* locale.cc (print_locale_with_codeset): Change way to retrieve
kernel32.dll path.