firmware: xilinx: Add sysfs support for feature config

Add support for sysfs interface for runtime features configuration.
 The user can configure the features at runtime. First, the user need
 to select the config id of the supported features and then the user
 can configure the parameters of the feature based on the config id.

Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Ronak Jain <ronak.jain@xilinx.com>
Link: https://lore.kernel.org/r/20220209082709.32378-4-ronak.jain@xilinx.com


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