examples : reduce initial memory to 512MB (ggml-org#2939)

* examples : reduce initial memory to 512MB

This commit reduces the initial memory size to 512MB. This is done to
to avoid WebAssembly memory allocation issues on some platforms. It also
adds a flag to allow the memory to grow dynamically (up to the maximum).

The motivation for this change is that currently the initial memory is
set to 2GB which might be to large for some platforms. This will lead to
an error being thrown from the JavaScript code generated by Emscripten
when trying to allocate memory. More details can be found in the
referenced issue below.


* examples : set MAXIMUM_MEMORY instead of TOTAL_MEMORY

This commit sets MAXIMUM_MEMORY instead of TOTAL_MEMORY in the
whisper.wasm example.

The motivation for this is that TOTAL_MEMORY and INITIAL_MEMORY are
actually the same thing. Instead we want to set MAXIMUM_MEMORY to
2GB. 

Refs: ggml-org#2920
Refs: https://emscripten.org/docs/tools_reference/settings_reference.html#initial-memory

ggml : add logging for native build options/vars (ggml-org#2935)

This commit adds debug level logging for the native build options and
variables to ggml/CMakeLists.txt.

The motivation for this is that it can be useful to see the effective
result of `GGML_NATIVE`, `GGML_NATIVE_DEFAULT`, and `INS_ENB` for a
cmake build. I've found myself adding similar logging a few times now,
so I thought it might be a good idea to add this.

Example output, specifying `-DCMAKE_MESSAGE_LOG_LEVEL=DEBUG` when
running cmake produces the following output:
```console
-- GGML_NATIVE         : OFF
-- GGML_NATIVE_DEFAULT : OFF
-- INS_ENB             : OFF
```

ci : remove CMAKE_CUDA_ARCHITECTURES in windows-cublas (ggml-org#2923)

This commit removes the -DCMAKE_CUDA_ARCHITECTURES=all flag from the
windows-cublas job in the build.yml file.

The motivation for this is that building for all architectures is
unnecessary and takes a long time. Without this flag the architectures
will instead be set by ggml-cuda.

Refs: ggml-org#2915 (comment)

xcframework : add support for CoreML to ios/macOS (ggml-org#2912)

* xcframework : add support for CoreML to ios/macOS

This commit add support for compiling whisper with CoreML support for
iOS and macOS.

The motivation for this change is it will allow users to use a Core ML
model or fall back to a ggml model if Core ML is not available.

With the updated xcframework, I was able to run the whisper.objc example
and successfully load a Core ML model:
```console
whisper_init_state: loading Core ML model from '/Users/danbev/Library/Developer/CoreSimulator/Devices/25E8C27D-0253-4281-AF17-C3F2A4D1D8F4/data/Containers/Bundle/Application/B81F6FF0-BF1A-40DF-AC2A-3908EC4BCC9A/whisper.objc.app/ggml-base.en-encoder.mlmodelc'
whisper_init_state: first run on a device may take a while ...
whisper_init_state: Core ML model loaded
```

* squash! xcframework : add support for CoreML to ios/macOS

Fix grammar in output message.