xilinx_hwicap: add support for virtex6 FPGAs

This patch adds support for the virtex6 FPGA to the xilinx_hwicap driver.

Tested on a Xilinx ML605 board. The patch is against the latest linus-tree.

Signed-off-by: Ariane Keller <ariane.keller@tik.ee.ethz.ch>
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>