VbNvStorage cleanup and comments

BUG=12282
TEST=make && make runtests

Review URL: http://codereview.chromium.org/6469059

Change-Id: I912b53ae33d65305353a747cc0bdd2b1ea62a04f
diff --git a/firmware/linktest/main.c b/firmware/linktest/main.c
index fbf4a2f..b171f19 100644
--- a/firmware/linktest/main.c
+++ b/firmware/linktest/main.c
@@ -10,6 +10,7 @@
 #include "tlcl.h"
 #include "vboot_common.h"
 #include "vboot_kernel.h"
+#include "vboot_nvstorage.h"
 
 
 int main(void)
@@ -79,5 +80,10 @@
   VerifyFirmwarePreamble(0, 0, 0);
   VerifyKernelPreamble(0, 0, 0);
 
+  VbNvSetup(0);
+  VbNvGet(0, 0, 0);
+  VbNvSet(0, 0, 0);
+  VbNvTeardown(0);
+
   return 0;
 }