netdev: ehea: port_lock semaphore to mutex

Convert the port_lock to a mutex.  There is also some additional cleanup.  The
line length inside the ehea_rereg_mrs was getting long so I made some
adjustments to shorten them.

[akpm@linux-foundation.org: dec99ification]
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Christoph Raisch <raisch@de.ibm.com>
Cc: Jan-Bernd Themann <themann@de.ibm.com>
Cc: Thomas Klein <tklein@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>