LIRC ioctl writeable calls should use ioctl_write_ptr!

calls such as lirc_sys::ioctl_lirc_set_rec_mode() fail as they translate to

ioctl(3, _IOC(_IOC_READ|_IOC_WRITE, 0x69, 0x19, 0x4), 0xbecbc07c)

where only _IOC_WRITE should be used. using ioctl_write_ptr! macro instead of ioctl_readwrite! solved this