Clean up the computation of the HCA context memory map.  This serves two
purposes:

 - make it easier to change the HCA "profile" (eg add more QPs)
 - make it easier to implement mem-free Arbel support
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>