[binutils-gdb] Remove internal_complaint

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 2b9496b2b4781b21bc30a70337e24205f8a923d8 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 2b9496b2b4781b21bc30a70337e24205f8a923d8

Remove internal_complaint

I happened to notice that gdb has both complaint_internal and
internal_complaint.  The latter is unused, so this patch removes it.

gdb/ChangeLog
2018-05-23  Tom Tromey  <tom@tromey.com>

	* complaints.c (internal_complaint): Remove.
	* complaints.h (internal_complaint): Remove.