Static layout: support image verification

Add support of image verification for static layout PNOR code update.

Tested: Verify the PNOR code update succeeds with valid-signed PNOR;
        and fails with invalid-signed PNOR or a PNOR tarball without
        signature.

Change-Id: I1aafeb4e8e07eaa16c170f33f4f21940f7c9c146
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/ubi/activation_ubi.cpp b/ubi/activation_ubi.cpp
index 9ce7085..5c57c4b 100644
--- a/ubi/activation_ubi.cpp
+++ b/ubi/activation_ubi.cpp
@@ -40,7 +40,7 @@
 
 #ifdef WANT_SIGNATURE_VERIFY
             // Validate the signed image.
-            if (!validateSignature())
+            if (!validateSignature(squashFSImage))
             {
                 // Cleanup
                 activationBlocksTransition.reset(nullptr);