[PCUDA] Initial support for AdaptiveCpp portable CUDA: A HIP/CUDA dialect for the generic JIT compiler (#1737)

* [SSCP] Store number of original kernel parameters in HCF

* Fix free kernel generation

* Start implementing runtime

* Avoid getAccessType for compatibility

* Finish wiring up kernel call

* Some support for host SLM

* Get kernel launch to work. More or less.

* Make cuda chevron launch optional feature

* Add missing files

* Fix pcudaFree API

* Improve compatibility of memory management API

* [PCUDA] Avoid duplicates in HCF format for host side parameter sizes

* Fix aggregate type handling for PCUDA kernel arguments

* [PCUDA] Add documentation

* [PCUDA] Add some LIT  tests

* [PCUDA] Improve handling of switching between platforms/backends

* [PCUDA] Implement more runtime API functionality

* [PCUDA] Implement event and StreamWaitEvent API

* Fix CI issues

* Enable PCUDA lit tests

* Fix chevron-launch LIT test

* [PCUDA] Add slm/dlm support

* Default to assume kernel dim=3 in case the hipsycl_kernel_dim annotation could not be found

* [SSCP][OpenMP] Consistently handle internal local memory subsections for globals

* [SSCP][llvm-to-host][PCUDA] Unfold constant expressions when replacing local mem GVs with builtin call

* [PCUDA] Update docs with slm/dlm support

* [PCUDA] Avoid llvm::SmalleDenseMap::contains() for compatibility

* [PCUDA] Remove trailing backslash in __global__ attribute

* Avoid race condition in prefer-group-size extension test

* [OpenMP] Capture dag node in submit_kernel to avoid lifetime issue

* [PCUDA] ExternDynamicLocalMemoryPass: Fix AS cast for LLVM < 17

* [CI] Enable PCUDA LIT tests for OpenMP

* [PCUDA] Fix free kernel argument handling for multi-parameter kernels

* [PCUDA][llvm-to-host] Fix ConstExpr unfolding for static local memory support

* [PCUDA] Add SLM LIT test case

* [PCUDA] Add DLM LIT test

* [PCUDA][NFC] Minor doc updates

* [PCUDA] Also perform constant expr unfolding for ExternDynamicLocalMemoryPass

* [PCUDA][llvm-to-spirv] Rewrite GEPs to zero-sized arrays to avoid llvm-spirv limitation

* Add some diagnostic output

* Remove diagnostics again

* [PCUDA] Add test cases for runtime API

* Add pcudaSetDeviceExt()

* [PCUDA][CI] Enable PCUDA API tests

* [PCUDA] Use GNU attribute syntax instead of [[clang::...]] for compatibility

* [PCUDA] Add pcudaGetDeviceProperties

* [PCUDA] Add pcudaGetErrorName/String

* [PCUDA] Add support for vector types

* [PCUDA] acpp: Improve handling of .cu files

* [PCUDA] C math functions to account for CUDA-flavored math stdlib behavior

* [PCUDA] Also provide cuda.h header

* [PCUDA] SLM: Look through ConstantExpr arguments when scanning for local memory annotation

* [PCUDA] Add pcudaThreadSynchronize()

* Fix missing synchronization in in-order queue test case

* [NFC][doc] Fix formatting

* Add PCUDA to mkdocs

* [PCUDA] Add pcudaHostAlloc

* [PCUDA] StreamDestroy: Fix typo in compatibility header

* [PCUDA] Add DriverGetVersion, PeekAtLastError, FreeHost

* [PCUDA] Fix copy-paste error in mapping of __pcudaGridDim

* [PCUDA] Fix bug in kernel launch and chevron LIT test case

* [PCUDA] Fix incorrect type in vector type definitions

* [PCUDA] Add Memset, MemsetAsync

* [NFC][doc] Update PCUDA documentation