python: Add checks for some more required python packages

This catches the most important packages we require, but
this may not be the full list.

python-gpg is not listed as we have a big workaround handler
for this in samba-tool.

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: David Mulder <dmulder@suse.com>

python/wscript

@@ -1,10 +1,18 @@
 #!/usr/bin/env python
 
 import os
+from waflib import Options, Errors
 
 # work out what python external libraries we need to be successful
 selftest_pkgs = {
     'iso8601': 'python3-iso8601',
+    'cryptography': 'python3-cryptography',
+    'pyasn1': 'python3-asn1'
+}
+
+ad_dc_pkgs = {
+    'markdown': 'python3-markdown',
+    'dns': 'python3-dnspython (python3-dns on some systems)'
 }
 
 
@@ -65,6 +73,10 @@ def configure(conf):
         for module, package in selftest_pkgs.items():
             find_third_party_module(conf, module, package)
 
+    if not Options.options.without_ad_dc:
+        for module, package in ad_dc_pkgs.items():
+            find_third_party_module(conf, module, package)
+
 
 def build(bld):