it exists, else check the time on the exec_bfd.
Fixes net buglet reported by Michael Snyder @ NeXT.
+Mon Jun 3 11:48:29 1996 Jeffrey A Law (law@cygnus.com)
+
+ * source.c (find_source_lines): Check the time on the symtab's bfd if
+ it exists, else check the time on the exec_bfd.
+
Thu May 30 09:43:17 1996 Mark Alexander <marka@cygnus.com>
* dsrec.c (make_srec): Fix calculation of address size