test: Add support for passing arguments to C tests

Add support for passing key=value arguments to unit tests. The test
framework parses arguments based on definitions provided by each test
and makes them available via uts->args[]

For now the 'ut' command does not support this new feature.

Co-developed-by: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>

arch/sandbox/cpu/spl.c

@@ -152,7 +152,8 @@ void spl_board_init(void)
 
 		ut_init_state(&uts);
 		ret = ut_run_list(&uts, "spl", NULL, tests, count,
-				  state->select_unittests, 1, false, NULL);
+				  state->select_unittests, 1, false, NULL,
+				  0, NULL);
 		ut_report(&uts.cur, 1);
 		ut_uninit_state(&uts);
 		/* continue execution into U-Boot */