[binutils-gdb] Eliminate obstack_printf

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT fdd243b001585c5ca078342608332af77050c867 ***

Author: Pedro Alves <palves@redhat.com>
Branch: master
Commit: fdd243b001585c5ca078342608332af77050c867

Eliminate obstack_printf

Not used anywhere.

gdb/ChangeLog:
2017-04-18  Pedro Alves  <palves@redhat.com>

	* xml-support.c (obstack_xml_printf): Delete.
	* xml-support.h (obstack_xml_printf): Delete.