You won't find any reference to OpenCL here,
https://developer.android.com/
So while those SDKs do exist, they aren't for application developers, rather for OEMs themselves.
You as application developer have zero control about what GPUs the customers might be using, there is no way to control it on Android manifests, only to specify what APIs are expected, which again, don't have OpenCL as part of the list.
https://developer.android.com/guide/topics/manifest/manifest...
So if you as application developer want to use said SDKs, it is only for your own device, most likely rooted, don't expect to sell applications on the store using OpenCL.
You are not allowed to ship drivers like that, and since version 7, there is kernel validation about stable NDK APIs.
So yeah just because there is an OpenCL SDK for Mali, doesn't mean that a random Android device with Mali will have the drivers or kernel support in place, because that isn't something that Android requires.
Google has collaborated with Adobe in porting their OpenCL shaders to Vulkan.
If they actually cared, they would have made OpenCL available instead.
I addition to the mentioned PowerVR and Intel platforms there seems to be Android OpenCL also for Mali and Adreno GPUs.
[1] https://apkpure.com/opencl%E2%84%A2-info/com.xh.openclinfo