patman: Avoid importing test_checkpatch before it is needed

Tests are not packaged with patman so this file will not be accessible
when installing with pip. Move the import later in the file, when we
know the file is present.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/tools/patman/__main__.py b/tools/patman/__main__.py
index 3063255..48ffbc8 100755 (executable)
--- a/tools/patman/__main__.py
+++ b/tools/patman/__main__.py
@@ -24,7 +24,6 @@ from patman import func_test
 from patman import gitutil
 from patman import project
 from patman import settings
-from patman import test_checkpatch
 from u_boot_pylib import terminal
 from u_boot_pylib import test_util
 from u_boot_pylib import tools
@@ -146,6 +145,7 @@ if not args.debug:
 # Run our meagre tests
 if args.cmd == 'test':
     from patman import func_test
+    from patman import test_checkpatch
 
     result = test_util.run_test_suites(
         'patman', False, False, False, None, None, None,