opticharger: skip packages labled as PRESIGNED

This fixes market updates and redundant
*.old files from being packaged- looks to
save about 10MB on the zip.

Change-Id: I82266204de3a04f71b24e4183672185d6b2da8d9
diff --git a/tools/opticharger b/tools/opticharger
index 79a5da6..9947db0 100755
--- a/tools/opticharger
+++ b/tools/opticharger
@@ -108,6 +108,11 @@
             echo "Unable to find certificate for $NAME"
             exit 1;
         fi
+        if [ "$CERT" = "PRESIGNED" ];
+        then
+            echo "$NAME is presigned, skipping"
+            exit 1;
+        fi
     fi
 
     [ $QUIET ] || echo "Certificate: $CERT";