tests: Add a simple test of the CMSDK APB watchdog

Add a simple test of the CMSDK watchdog, since we're about to do some
refactoring of how it is clocked.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210128114145.20536-5-peter.maydell@linaro.org
Message-id: 20210121190622.22000-5-peter.maydell@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 6c15f7d..3729b89 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -588,6 +588,7 @@
 F: include/hw/char/cmsdk-apb-uart.h
 F: hw/watchdog/cmsdk-apb-watchdog.c
 F: include/hw/watchdog/cmsdk-apb-watchdog.h
+F: tests/qtest/cmsdk-apb-watchdog-test.c
 F: hw/misc/tz-ppc.c
 F: include/hw/misc/tz-ppc.h
 F: hw/misc/tz-mpc.c