Add python-gdb.py and python.exe-gdb.py to distclean target in Makefile.

Makefile.pre.in

@@ -1192,6 +1192,7 @@ distclean: clobber
 	-rm -f core Makefile Makefile.pre config.status \
 		Modules/Setup Modules/Setup.local Modules/Setup.config \
 		Misc/python.pc
+	-rm -f python*-gdb.py
 	find $(srcdir) '(' -name '*.fdc' -o -name '*~' \
 			   -o -name '[@,#]*' -o -name '*.old' \
 			   -o -name '*.orig' -o -name '*.rej' \