watchdog: aspeed: fix hardware timeout calculation

watchdog: aspeed: fix hardware timeout calculation

BugLink: https://bugs.launchpad.net/bugs/1939440
[ Upstream commit e7dc481c92060f9ce872878b0b7a08c24713a7e5 ]

Fix hardware timeout calculation in aspeed_wdt_set_timeout function to
ensure the reload value does not exceed the hardware limit.

Fixes: efa859f7d786 ("watchdog: Add Aspeed watchdog driver")
Reported-by: Amithash Prasad <amithash@fb.com>
Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210417034249.5978-1-rentao.bupt@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>