David Brownell <david-b@pacbell.net> More fixes from test cases:

       A5.3.8 Load halfword, unallocated memory hints

It's mostly the usual sort of bitmasking goofage and getting the
width specs right.  In one case an older x86 GCC generated bad code
unless I structred a conditional differently (sigh).

git-svn-id: svn://svn.berlios.de/openocd/trunk@2566 b42882b7-edfa-0310-969c-e2dbd0fdcd60