md_monitor: Reset ioctl flags when re-starting monitor

When the monitor for a DASD is started we need to reset
the ioctl flag; otherwise a stale flag will never be reset
and the array will hang. On the same ground we should be
resetting the flag when the monitor thread is terminated.

References: bnc#817805

Signed-off-by: Hannes Reinecke <hare@suse.de>
md_monitor: Increase the number of open files

Add option '-O' to increase the number of open files. Default
is set to 4096.

References: bnc#820146

Signed-off-by: Hannes Reinecke <hare@suse.de>
md_monitor: Update documentation

Update manpage and help text to reflect latest changes.

Signed-off-by: Hannes Reinecke <hare@suse.de>
monitor_testcase_5: Chpid on/off

Test for chpid on/off.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Version 4.23

Signed-off-by: Hannes reinecke <hare@suse.de>