Cleanup out-or-tree building for some boards (.depend)

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/cray/L1/Makefile b/board/cray/L1/Makefile
index cfdd60e..21b513c 100644
--- a/board/cray/L1/Makefile
+++ b/board/cray/L1/Makefile
@@ -43,7 +43,7 @@
 		$(obj)bootscript.image $(obj)bootscript.o
 
 distclean:	clean
-	rm -f $(LIB) core *.bak .depend
+	rm -f $(LIB) core *.bak $(obj).depend
 
 $(obj)$(BOARD).o : $(src)$(BOARD).c $(obj)bootscript.o