audio: Favor OpenSL ES over AAudio.
There are low-latency fixes in SDL3 that really need to be backported to SDL2
before AAudio will be nicer across a range of devices, so OpenSL ES is safer
in SDL2 at the moment. At least, we suspect as such.
Fixes #11457.
(cherry picked from commit 17b9ed7d82503bdd342e3d3973929e519b846804)