cdx: add sysfs for bus reset

Add sysfs interface reset to reset all the devices on the CDX bus.

Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Link: https://lore.kernel.org/r/20231017160505.10640-7-abhijit.gangurde@amd.com


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