Fix scancode comment concerning key release
Fix scancode comment concerning key release

According to the scancode reference, the release key code is generated by
adding `0x80` to the key press code, not `0x81`.

suma/packer,patricklucas/packer,Kaixiang/packer,Kaixiang/packer,suma/packer,suma/packer,patricklucas/packer,Kaixiang/packer,patricklucas/packer,TranscendComputing/packer,suma/packer,TranscendComputing/packer,TranscendComputing/packer,Kaixiang/packer,TranscendComputing/packer,patricklucas/packer