GenWQE Sysfs interfaces

Sysfs interfaces for the GenWQE card. There are attributes to query
the version of the bitstream as well as some for the driver. For
debugging, please also see the debugfs interfaces of this driver.

Signed-off-by: Frank Haverkamp <haver@linux.vnet.ibm.com>
Co-authors: Joerg-Stephan Vogt <jsvogt@de.ibm.com>,
            Michael Jung <MIJUNG@de.ibm.com>,
            Michael Ruettger <michael@ibmra.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>