rtc: SetTime. payload len set from zero to proper length

Since the payload length was always set to zero, the message to set the time on the hardware RTC was never correctly parsed.

Signed-off-by: Christina Quast <chrysh.ng+github@gmail.com>
rtc: Removed unused IOCTL function implementation

The functions read_time and set_time of a RTC device are normally called instead of the IOCTL function.

Signed-off-by: Christina Quast <chrysh.ng+github@gmail.com>