Fix checkpatch ERROR and CHECK in core/rtw_iol.c

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Delete dead code inside regions that require CONFIG_IOL to be defined

This change also deletes the now unused files core/rtw_iol.c and
include/rtw_iol.h.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>