firmware: xilinx: add support for sd/gem config

Add new APIs in firmware to configure SD/GEM registers. Internally
it calls PM IOCTL for below SD/GEM register configuration:
- SD/EMMC select
- SD slot type
- SD base clock
- SD 8 bit support
- SD fixed config
- GEM SGMII Mode
- GEM fixed config

Signed-off-by: Ronak Jain <ronak.jain@xilinx.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>