misc: xilinx_sdfec: Add ability to get/set config

- Add capability to get SD-FEC config data using ioctl
XSDFEC_GET_CONFIG.

- Add capability to set SD-FEC data order using ioctl
SDFEC_SET_ORDER.

- Add capability to set SD-FEC bypass option using ioctl
XSDFEC_SET_BYPASS.

- Add capability to set SD-FEC active state using ioctl
XSDFEC_IS_ACTIVE.

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Link: https://lore.kernel.org/r/1564216438-322406-5-git-send-email-dragan.cvetic@xilinx.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>