fpga: dfl: fme: add partial reconfiguration sub feature support

Partial Reconfiguration (PR) is the most important function for FME. It
allows reconfiguration for given Port/Accelerated Function Unit (AFU).

It creates platform devices for fpga-mgr, fpga-regions and fpga-bridges,
and invokes fpga-region's interface (fpga_region_program_fpga) for PR
operation once PR request received via ioctl. Below user space interface
is exposed by this sub feature.

Ioctl interface:
* DFL_FPGA_FME_PORT_PR
  Do partial reconfiguration per information from userspace, including
  target port(AFU), buffer size and address info. It returns error code
  to userspace if failed. For detailed PR error information, user needs
  to read fpga-mgr's status sysfs interface.

Signed-off-by: Tim Whisonant <tim.whisonant@intel.com>
Signed-off-by: Enno Luebbers <enno.luebbers@intel.com>
Signed-off-by: Shiva Rao <shiva.rao@intel.com>
Signed-off-by: Christopher Rauer <christopher.rauer@intel.com>
Signed-off-by: Kang Luwei <luwei.kang@intel.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>