Make lockmem a per job option

We need to get rid of per job options that fiddle with global
state. It's confusing, and it breaks remote option handling.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Conflicts:
	backend.c
	fio.h
	init.c
	options.c

Signed-off-by: Jens Axboe <axboe@kernel.dk>
ioengine: import whitespace changes

Signed-off-by: Jens Axboe <axboe@kernel.dk>