debian/rules: remove config.log when cleaning

This allows building twice in a source tree that is not a git clone
(e.g. after running apt-get source in a porterbox).

Author: terceiro

debian/rules

@@ -102,7 +102,7 @@ override_dh_auto_clean:
 	$(RM) -r .ext
 	$(RM) -r doc/capi
 	$(RM) .installed.list GNUmakefile Makefile builtin_binary.inc \
-		config.status enc.mk uncommon.mk verconf.h
+		config.status enc.mk uncommon.mk verconf.h config.log
 
 override_dh_auto_build-arch:
 	dh_auto_build -- main V=1