doc: fpga-mgr: add fpga image info to api

This patch adds a minor change in the FPGA Manager API
to hold information that is specific to an FPGA image
file.  This change is expected to bring little, if any,
pain.

An FPGA image file will have particulars that affect how the
image is programmed to the FPGA.  One example is that
current 'flags' currently has one bit which shows whether the
FPGA image was built for full reconfiguration or partial
reconfiguration.  Another example is timeout values for
enabling or disabling the bridges in the FPGA.  As the
complexity of the FPGA design increases, the bridges in the
FPGA may take longer times to enable or disable.

This patch documents the change in the FPGA Manager API
functions, replacing the 'u32 flag' parameter with a pointer
to struct fpga_image_info.

Signed-off-by: Alan Tull <atull@opensource.altera.com>
Acked-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>