Fix GDB build without expat

An earlier patch of mine changed parse_traceframe_info to make it return
a unique_ptr.  I forgot to update the version of the function used in an
expat-less build, this patch fixes it.

gdb/ChangeLog:

	* tracepoint.c (parse_traceframe_info): Return a unique_ptr
	(the !HAVE_LIBEXPAT version).
2 files changed