usb: clock_control: Fix symbol when getting mgr for HFCLK
usb: clock_control: Fix symbol when getting mgr for HFCLK

When getting a hfxo manager for USB sybsystem incorrect symbol
was checked. This lead to always enabling HFCLK, even for nRF5340
which needs HFCLK192M.

Signed-off-by: Emil Obalski <a38006c9a9911dcd7c7e26537de6a2fa1043ca9e@nordicsemi.no>

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