stm32: Use DT_NUM_INST_STATUS_OKAY for num IRQ sources
stm32: Use DT_NUM_INST_STATUS_OKAY for num IRQ sources

Use DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) to determine
number of potential interrupt sources. This mitigates
the wasting of memory on devices with mutliple UCPD ports
but only one UCPD port is used.

Signed-off-by: Sam Hurst <f5a9a7a3c43e6bdd2ccfb8b7fc2e1bb9f1b6bcb2@gmail.com>

finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr