drivers: modem: hl7800: do not require DEVICE_POWER_MANAGEMENT
drivers: modem: hl7800: do not require DEVICE_POWER_MANAGEMENT

Remove requirement for DEVICE_POWER_MANAGEMENT,
the driver does not need it to operate.

Signed-off-by: Ryan Erickson <445db09b136432317bdbb8e4308a30651390c2e2@lairdconnect.com>
finikorg/zephyr,galak/zephyr,nashif/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,Vudentz/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,nashif/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,nashif/zephyr,finikorg/zephyr,Vudentz/zephyr,Vudentz/zephyr,finikorg/zephyr