scripts: Allow image version number

Add an --image-version argument to zep2newt.py to allow the major
version number to be set.  This helps make testing easier by having
differing version numbers.

scripts/zep2newt.py

@@ -63,6 +63,9 @@ def get_args():
     parser.add_argument('-f', required=False, action="store_true", \
                         default=False, \
                         help='Flash using JLinkExe')
+    parser.add_argument('--image-version', dest='image_version',
+            default=1,
+            help='Major part of version number')
 
     return parser.parse_args()
 
@@ -189,7 +192,7 @@ class Convert():
                 self.vtable_offs,
                 image_size,
                 sig.get_flags(),
-                1, 0, 0, 0)
+                int(self.args.image_version), 0, 0, 0)
         return hd
 
     def add_trailer(self, pad):

sign.sh

@@ -9,6 +9,7 @@ source $(dirname $0)/target.sh
     --out shell.signed.bin \
     --vtoff 0x200 \
     --word-size 8 \
+    --image-version 3 \
     --bit --pad 0x20000
 
 ./scripts/zep2newt.py \
@@ -17,4 +18,5 @@ source $(dirname $0)/target.sh
     --sig RSA \
     --vtoff 0x200 \
     --word-size 8 \
+    --image-version 2 \
     --out hello.signed.bin