[llvm] [OFFLOAD] Add support for host offloading device (PR #177307)

[via llvm-commits]

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@@ -12,7 +12,9 @@
 
 #include <cassert>
 #include <cstddef>
+#if !defined(SKIP_FFI_BUILD)
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fineg74 wrote:

The idea was to skip compilation of ffi completely on platforms that are not supported and this is done in CMakeLists for the host plugin so in this case the plugin will serve primarily as a memcpy target with ability to load and run any kernels completely disabled. The concern is that on unsupported platforms, compilation of ffi may fail breaking the entire build. 

https://github.com/llvm/llvm-project/pull/177307