sandbox: disable CONFIG_WATCHDOG_AUTOSTART

For the unit tests, it is more convenient if the tests are in charge
of when the watchdog devices are started and stopped, so prevent
wdt-uclass from doing it automatically.

Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index ea08a9e..ec6b1c2 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -281,6 +281,7 @@
 CONFIG_W1_GPIO=y
 CONFIG_W1_EEPROM=y
 CONFIG_W1_EEPROM_SANDBOX=y
+# CONFIG_WATCHDOG_AUTOSTART is not set
 CONFIG_WDT=y
 CONFIG_WDT_SANDBOX=y
 CONFIG_FS_CBFS=y