imgtool: Update version.py to take command line arguments

Main method printed hardcoded versions, update to take argument
to enable the possibility of testing version strings by invoking
the command through command line.

Signed-off-by: Rustam Ismayilov <rustam.ismayilov@arm.com>
Change-Id: If75769ef223944865313ed95336e859ebef85fd6

scripts/imgtool/version.py

@@ -1,4 +1,5 @@
 # Copyright 2017 Linaro Limited
+# Copyright 2024 Arm Limited
 #
 # SPDX-License-Identifier: Apache-2.0
 #
@@ -20,9 +21,9 @@
 Implements a subset of semantic versioning that is supportable by the image
 header.
 """
-
-from collections import namedtuple
 import re
+import sys
+from collections import namedtuple
 
 SemiSemVersion = namedtuple('SemiSemVersion', ['major', 'minor', 'revision',
                                                'build'])
@@ -49,7 +50,7 @@ def decode_version(text):
 
 
 if __name__ == '__main__':
-    print(decode_version("1.2"))
-    print(decode_version("1.0"))
-    print(decode_version("0.0.2+75"))
-    print(decode_version("0.0.0+00"))
+    if len(sys.argv) > 1:
+        print(decode_version(sys.argv[1]))
+    else:
+        print("Requires an argument, e.g. '1.0.0'")