use distclean in BUILD/compile* scripts to make sure .deps dirs go

away (old .Plo files in them showed to cause build problems for at
least another dev and me, and they also cause problems after .c->.cc
renames).

BUILD/FINISH.sh

@@ -10,7 +10,7 @@ do
 done
 
 commands="\
-$make -k clean || true 
+$make -k distclean || true 
 /bin/rm -rf */.deps/*.P config.cache innobase/config.cache bdb/build_unix/config.cache bdb/dist/autom4te.cache autom4te.cache innobase/autom4te.cache;
 
 aclocal    || (echo \"Can't execute aclocal\"     && exit 1)