utils/scanpypi: search LICENSE.MD

Some packages such as python-idna has a LICENSE.md file:
https://github.com/kjd/idna/blob/master/LICENSE.md

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 60aa896904c0d8a07d6fbbf7e90b7f9efd196678)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

utils/scanpypi

@@ -495,8 +495,8 @@ class BuildrootPackage():
         """
         lines = []
 
-        filenames = ['LICENCE', 'LICENSE', 'LICENSE.RST', 'LICENSE.TXT',
-                     'COPYING', 'COPYING.TXT']
+        filenames = ['LICENCE', 'LICENSE', 'LICENSE.MD', 'LICENSE.RST',
+                     'LICENSE.TXT', 'COPYING', 'COPYING.TXT']
         self.license_files = list(find_file_upper_case(filenames, self.tmp_extract))
 
         lines.append(self.__get_license_names(self.license_files))