Introducing experimental OpenCL backend with support for Qualcomm Adreno GPUs (llama...

Introducing experimental OpenCL backend with support for Qualcomm Adreno GPUs (llama/10693)

* [cl][adreno] Add Adreno GPU support

Add new OpenCL backend to support Adreno GPUs

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Co-authored-by: Skyler Szot <redacted>
Co-authored-by: Shangqing Gu <redacted>
Co-authored-by: Alexander Angus <redacted>
Co-authored-by: Hongqiang Wang <redacted>
Co-authored-by: Max Krasnyansky <redacted>
* [cl][ci] Add workflow for CL

* [cl][adreno] Fix memory leak for non SMALL_ALLOC path

* opencl: integrate backend dyn.load interface and fix compiler and format warnings

* opencl: remove small-alloc support and fix build errors for non-opencl platforms

* opencl: fixed merge conflict (MUSA added twice in cmake)

* opencl-ci: use RUNNER_TEMP instead of github.workspace

* opencl: fix embed tool invocation with python3

* opencl: CI workflow fixes

* opencl: Clean up small-alloc in CMake files

* opencl: cleanup ggml-opencl2 header file

* opencl: use ulong for offsets and strides in ADD kernel

* opencl: use cl_ulong for all offsets

* opencl: use cl_ulong for sizes and strides

* opencl: use `GGML_LOG_xxx` instead of `fprintf(stderr, ...)`

* opencl: rename backend `opencl2` -> `opencl`

* opencl: rename kernel files `ggml-opencl2` -> `ggml-opencl`

* opencl: make OpenCL required, remove redundant lib and inc directories

* `ggml-base`, `..` and `.` are added by `ggml_add_backend_library`

* opencl: rename backend - funcs, structs, etc `opencl2` -> `opencl`

* opencl: remove copyright marker since main license already covers

* opencl: replace some more OPENCL2 leftovers

* opencl: remove limits on `tensor_extra`

* opencl: use pools for `tensor_extra`

* opencl: fix compiler warnings with GCC and Clang

Still getting the warning about clCreateCmdQueue being obsolete.
Will fix that separately.

* opencl: fail gracefully if opencl devices are not available

Also for unsupported GPUs.

* opencl: fix MSVC builds (string length error)

* opencl: check for various requirements, allow deprecated API

* opencl: update log message for unsupported GPUs

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Co-authored-by: Skyler Szot <redacted>
Co-authored-by: Shangqing Gu <redacted>
Co-authored-by: Alexander Angus <redacted>
Co-authored-by: Hongqiang Wang <redacted>
Co-authored-by: Max Krasnyansky <redacted>