Add argparse with help.

tools/onlplatform.py

@@ -8,6 +8,7 @@ the platform package metadata.
 
 import sys, os
 import itertools
+import argparse
 
 toolsdir = os.path.dirname(os.path.abspath(__file__))
 sys.path.append(toolsdir)
@@ -23,9 +24,11 @@ from onlpm import *
 
 pm = defaultPm()
 
-platform = sys.argv[1]
-arch = sys.argv[2]
-key = sys.argv[3]
+ap = argparse.ArgumentParser("ONL Platform Data Extractor.")
+ap.add_argument("platform", help="Platform name")
+ap.add_argument("arch", help="Architecture")
+ap.add_argument("key", help="Lookup key.")
+ops = ap.parse_args()
 
 def extractKey(platform, arch, key):
 
@@ -71,12 +74,12 @@ def extractVendor(platform, arch):
     l = [x for x in l if x.startswith('onl-vendor-config-')]
     return "\n".join(l)
 
-if key in ('kernel', 'initrd', 'dtb', 'itb',):
-    print extractKey(platform, arch, key)
+if ops.key in ('kernel', 'initrd', 'dtb', 'itb',):
+    print extractKey(ops.platform, ops.arch, ops.key)
     sys.exit(0)
 
-if key == 'vendor':
-    print extractVendor(platform, arch)
+if ops.key == 'vendor':
+    print extractVendor(ops.platform, ops.arch)
     sys.exit(0)
 
-raise SystemExit("invalid key %s" % key)
+raise SystemExit("invalid key %s" % ops.key)