Added top level makefile

verilog/dv/Makefile

diff --git a/verilog/dv/Makefile b/verilog/dv/Makefile
index 7895a6e..73d7868 100644
--- a/verilog/dv/Makefile
+++ b/verilog/dv/Makefile
@@ -30,5 +30,6 @@
 	for i in ${PATTERNS}; do \
 		( cd $$i && make clean ) ; \
 	done
-
+	rm -rf *.log
+	
 .PHONY: clean all