fjes: Add debugfs entry for EP status information in fjes driver

This patch adds debugfs entry to show EP status information.
You can get each EP's status information like the following:

  # cat /sys/kernel/debug/fjes/fjes.0/status

EPID    STATUS           SAME_ZONE        CONNECTED
ep0     shared           Y                Y
ep1     -                -                -
ep2     unshared         N                N
ep3     unshared         N                N
ep4     unshared         N                N
ep5     unshared         N                N
ep6     unshared         N                N
ep7     unshared         N                N

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>