test/py: Shorten u_boot_console

This fixture name is quite long and results in lots of verbose code.
We know this is U-Boot so the 'u_boot_' part is not necessary.

But it is also a bit of a misnomer, since it provides access to all the
information available to tests. It is not just the console.

It would be too confusing to use con as it would be confused with
config and it is probably too short.

So shorten it to 'ubman'.

Signed-off-by: Simon Glass <sjg@chromium.org>
Link: https://lore.kernel.org/u-boot/CAFLszTgPa4aT_J9h9pqeTtLCVn4x2JvLWRcWRD8NaN3uoSAtyA@mail.gmail.com/
diff --git a/test/py/tests/test_of_migrate.py b/test/py/tests/test_of_migrate.py
index 910f7c0..3b0fa2f 100644
--- a/test/py/tests/test_of_migrate.py
+++ b/test/py/tests/test_of_migrate.py
@@ -61,9 +61,9 @@
 
 @pytest.mark.slow
 @pytest.mark.boardspec('sandbox')
-def test_of_no_migrate(u_boot_console):
+def test_of_no_migrate(ubman):
     """Test sandbox with old boot phase tags like u-boot,dm-pre-proper"""
-    cons = u_boot_console
+    cons = ubman
 
     build_for_migrate(cons, ['bootph-some-ram', 'u-boot,dm-pre-proper'],
                       'sandbox', TMPDIR1)
@@ -80,9 +80,9 @@
 @pytest.mark.boardspec('sandbox_spl')
 @pytest.mark.boardspec('spl_of_platdata_inst')
 @pytest.mark.boardspec('!sandbox_tpl')
-def test_of_no_migrate_spl(u_boot_console):
+def test_of_no_migrate_spl(ubman):
     """Test sandbox with old boot phase tags like u-boot,dm-spl"""
-    cons = u_boot_console
+    cons = ubman
 
     out = build_for_migrate(cons, ['bootph-pre-ram', 'u-boot,dm-spl'],
                             'sandbox_spl', TMPDIR2)
@@ -94,9 +94,9 @@
 
 @pytest.mark.slow
 @pytest.mark.boardspec('sandbox')
-def test_of_migrate(u_boot_console):
+def test_of_migrate(ubman):
     """Test sandbox shows a message when tags were migrated"""
-    cons = u_boot_console
+    cons = ubman
 
     build_for_migrate(cons, ['bootph-some-ram', 'u-boot,dm-pre-proper'],
                       'sandbox', TMPDIR3, disable_migrate=False)