On real hardware, stswi and stswx don't trigger any of the special
behavior for uncached unaligned writes that was implemented in 543ed8a.
This is confirmed by a hwtest (a new commit in
https://github.com/dolphin-emu/hwtests/pull/42).
This change fixes Dolphin's stswi and stswx implementations so they stop
triggering the special behavior, bringing them back to the behavior they
had before 543ed8a. No games are known to be affected, but Extrems has
reported that it affects homebrew they've made.
2b376a92ae