Add header guard to several header files.

2014-09-19  Kito Cheng  <kito@0xlab.org>

	* except.h: Fix header guard.
	* addresses.h: Add missing header guard.
	* cfghooks.h: Likewise.
	* collect-utils.h: Likewise.
	* collect2-aix.h: Likewise.
	* conditions.h: Likewise.
	* cselib.h: Likewise.
	* dwarf2asm.h: Likewise.
	* graphds.h: Likewise.
	* graphite-scop-detection.h: Likewise.
	* gsyms.h: Likewise.
	* hw-doloop.h: Likewise.
	* incpath.h: Likewise.
	* ipa-inline.h: Likewise.
	* ipa-ref.h: Likewise.
	* ira-int.h: Likewise.
	* ira.h: Likewise.
	* lra-int.h: Likewise.
	* lra.h: Likewise.
	* lto-section-names.h: Likewise.
	* read-md.h: Likewise.
	* reload.h: Likewise.
	* rtl-error.h: Likewise.
	* sdbout.h: Likewise.
	* targhooks.h: Likewise.
	* tree-affine.h: Likewise.
	* xcoff.h: Likewise.
	* xcoffout.h: Likewise.

From-SVN: r215365