Initial work on provided correctly aligned __cpu_simple_lock_t for hppa
and first attempt at adapting i386 to the changes.

More to come.
Get the aligned word of the mtx_lock in mutex_enter/mutex_exit.
Provide __SIMPLELOCK_{UN,}LOCKED_P and __cpu_simple_lock_{set,clear}
for all architectures.
Simplify the pthread__simple_lock_try RAS.
Use HPPA_LDCW_ALIGN instead of magic constant.
Sync with HEAD.
Sync with HEAD.
Sprinkle volatile.
Sync with HEAD.
Sync with HEAD.
Adapt some more code to the branch.
Sync with HEAD.
Fix inverted test.
Reduce diff to HEAD.