K 10
svn:author
V 3
mav
K 8
svn:date
V 27
2016-12-29T15:09:34.302432Z
K 7
svn:log
V 269
Improve use of I/O's private area.

 - Since I/Os are allocates from per-port pools, make allocations store
pointer to CTL softc there, and use it where needed instead of global.
 - Created bunch of helper macros to access LUN, port and CTL softc.

MFC after:	 2 weeks

END