add FPGA manager core

API to support programming FPGA's.

The following functions are exported as GPL:
* fpga_mgr_buf_load
   Load fpga from image in buffer

* fpga_mgr_firmware_load
   Request firmware and load it to the FPGA.

* fpga_mgr_register
* fpga_mgr_unregister
   FPGA device drivers can be added by calling
   fpga_mgr_register() to register a set of
   fpga_manager_ops to do device specific stuff.

* of_fpga_mgr_get
* fpga_mgr_put
   Get/put a reference to a fpga manager.

The following sysfs files are created:
* /sys/class/fpga_manager/<fpga>/name
  Name of low level driver.

* /sys/class/fpga_manager/<fpga>/state
  State of fpga manager

Signed-off-by: Alan Tull <atull@opensource.altera.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>