objc.texi: Move from ../libobjc/objc-features.texi.
gcc:
* objc.texi: Move from ../libobjc/objc-features.texi. Adjust for
inclusion as a chapter of the GCC manual.
* gcc.texi: Include objc.texi.
* fdl.texi: Use @unnumberedsec for the addendum.
* Makefile.in ($(srcdir)/gcc.info, gcc.dvi): Update dependencies.
libobjc:
* objc-features.texi: Move to ../gcc/objc.texi.
* fdl.texi: Remove.
* Makefile.in: Don't generate documentation from
objc-features.texi.