fpga: zynqmp-fpga: Adds status interface

Adds status interface for zynqmp-fpga. It's a read only interface
which allows the user to get the Programmable Logic(PL) configuration
status.

Usage:
To read the Programmable Logic(PL) configuration status.
cat /sys/bus/platform/drivers/zynqmp_fpga_manager/firmware:zynqmp-firmware:pcap/status

Signed-off-by: Nava kishore Manne <nava.kishore.manne@amd.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20230224120738.329416-3-nava.kishore.manne@amd.com


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