build: Revert "build: fix make checkstyle"

This reverts commit 069e2a734cf75f4d151efe49d1efc51bc82cedb2.

Reason for revert: The vpp-verify-checkstyle-master build executor now
runs 'make install-dep'

Type: fix

Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
Change-Id: I2ab6bee642b7ed631d2aa06203c76c3d0ca01c9e
diff --git a/Makefile b/Makefile
index 6788a3c..7f5092b 100644
--- a/Makefile
+++ b/Makefile
@@ -559,7 +559,7 @@
 
 checkstyle:
 	@build-root/scripts/checkstyle.sh
-	#yamllint $(WS_ROOT)/src
+	yamllint $(WS_ROOT)/src
 
 fixstyle:
 	@build-root/scripts/checkstyle.sh --fix