Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series1/EFM32GG11B/EFM32GG11B510F2048GQ100/GPIO/IFC#0x0
Interrupt Flag Clear Register
Clear EXT Interrupt Flag
Clear EM4WU Interrupt Flag
https://github.com/cmsis-svd/cmsis-svd-data