staging: lustre: open code polling loop instead of using l_wait_event()

Two places that LWI_TIMEOUT_INTERVAL() is used, the outcome is a
simple polling loop that polls every second for some event (with a
limit).

So write a simple loop to make this more apparent.

Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Patrick Farrell <paf@cray.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>