config.gcc (i[34567]86-*-linux*): Handle --enable-targets=all.

gcc:
	* config.gcc (i[34567]86-*-linux*): Handle --enable-targets=all.
	Handle tuning for bi-arch i[34567]86-*-linux* like that for
	i[34567]86-*-solaris2.1[0-9]*.
	* config/i386/linux64.h (TARGET_VERSION, MULTILIB_DEFAULTS):
	Define conditionally depending on TARGET_64BIT_DEFAULT.
	(SPEC_32, SPEC_64): Define.
	(LINK_SPEC): Use them.
	* doc/install.texi (--enable-targets=all): Document for x86-linux.

libcpp:
	* configure.ac (need_64bit_hwint): Set for i[34567]86-*-linux*
	depending on --enable-targets=all.
	* configure: Regenerate.

fixincludes:
	* inclhack.def (AAB_fd_zero_asm_posix_types_h): Bypass on x86_64.
	* fixincl.x: Regenerate.

From-SVN: r118147