gdb: move lm_info to solib in dsbt_current_sos

Commit 8971d2788e ("gdb: link so_list using intrusive_list")
mistakenly removed the line that moves the lm_info unique pointer to
sop->lm_info, probably due to a bad conflict resolution.  Restore that
line.

Unfortunately, this code is only used for TI C66, which is not widely
tested (if used at all).

Change-Id: I9f64eb4430c324bc93ddb4bd00d820dee34adfbb
Approved-By: Tom Tromey <tom@tromey.com>

gdb/solib-dsbt.c

@@ -616,6 +616,7 @@ dsbt_current_sos (void)
 	      sop->so_original_name = sop->so_name;
 	    }
 
+	  sop->lm_info = std::move (li);
 	  sos.push_back (*sop);
 	}
       else