fe0e2907b3
This reverts part of 36cda3b3116acba3b895daf68689f8af01b62392 and replaces the use of `OB_MODE_PAINT_GREASE_PENCIL` `OB_MODE_PAINT_GPENCIL_LEGACY` flag instead. The `OB_MODE_PAINT_GREASE_PENCIL` is removed. The `GREASE_PENCIL_OT_draw_mode_toggle` operator is removed and the `GPENCIL_OT_paintmode_toggle` operator is adapted to work with GPv3. Pull Request: https://projects.blender.org/blender/blender/pulls/121027