Backport terrain on Adreno (620, 640&650) crash workaround (use floating point textures or terrain)

In came cases, terrain would flicker when panning or zooming and, after some time, make the map not responsive or crash the browser view on some of the Adreno powered Android devices.

It seems that on every flicker frame, logcat prints:

021-03-30 08:33:43.740 11340-11501/com.mapbox.mapboxsdk.maps.shell W/Adreno-GSL: <gsl_ldd_control:553>: ioctl fd 89 code 0xc040094a (IOCTL_KGSL_GPU_COMMAND) failed: errno 71 Protocol error
2021-03-30 08:33:43.740 11340-11501/com.mapbox.mapboxsdk.maps.shell W/Adreno-GSL: <log_gpu_snapshot:462>: panel.gpuSnapshotPath is not set.not generating user snapshot

Finally, on freezing:

021-03-30 08:33:43.740 11340-11501/com.mapbox.mapboxsdk.maps.shell W/Adreno-GSL: <gsl_ldd_control:553>: ioctl fd 89 code 0xc040094a (IOCTL_KGSL_GPU_COMMAND) failed: errno 71 Protocol error
2021-03-30 08:33:43.740 11340-11501/com.mapbox.mapboxsdk.maps.shell W/Adreno-GSL: <log_gpu_snapshot:462>: panel.gpuSnapshotPath is not set.not generating user snapshot

The workaround has been verified in gl-native, using GL_FLOAT textures based on https://github.com/mapbox/mapbox-gl-js/pull/10652.

cc @guchan-fout

Start by reviewing the verified gl-native workaround and the referenced mapbox-gl-js pull request #10652, focusing on the use of GL_FLOAT textures for terrain. Confirm the change on Adreno 620, 640, and 650 Android devices; done means terrain no longer flickers, freezes the map, or crashes the browser view.