Sync top level files with gcc.

Sync top level files with gcc.

	Import these patches from the GCC mainline:

	2016-01-12  Andris Pavenis  <andris.pavenis@iki.fi>

	* configure.ac: Enable LTO for DJGPP
	* configure: Regenerate

	2016-01-24  Mikhail Maltsev  <maltsevm@gmail.com>

	PR bootstrap/69329
	* Makefile.tpl (BASE_FLAGS_TO_PASS): Add LSAN_OPTIONS.
	* Makefile.in: Regenerate.

	2016-01-25  Aditya Kumar  <aditya.k7@samsung.com>
	            Sebastian Pop  <s.pop@samsung.com>

	* Makefile.in: Regenerate.
	* Makefile.tpl: Export ISLVER.
	* configure: Regenerate.
	* config/isl.m4: Detect isl-0.15.

	2016-01-29  Sebastian Pop  <s.pop@samsung.com>

	* config/isl.m4: Add comments about isl-0.16.
	* configure: Regenerate.