clocksource/drivers/stm32-lptimer: Use wakeup capable instead of init wakeup

"wakeup-source" property describes a device which has wakeup capability
but should not force this device as a wakeup source.

Fixes: 48b41c5e ("clocksource: Add Low Power STM32 timers driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Rule: add
Link: https://lore.kernel.org/stable/20250306083407.2374894-1-fabrice.gasnier%40foss.st.com
Link: https://lore.kernel.org/r/20250306102501.2980153-1-fabrice.gasnier@foss.st.com


Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>