[libclc] [libclc] Fix commands in compile_to_bc are executed sequentially (PR #130755)

[Wenju He via cfe-commits]

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@@ -63,13 +65,15 @@ function(compile_to_bc)
       ${ARG_DEPENDENCIES}
     DEPFILE ${ARG_OUTPUT}.d
   )
+  add_custom_target( ${ARG_TARGET} DEPENDS ${ARG_OUTPUT}${TMP_SUFFIX} )
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wenju-he wrote:

I have simplified the code by removing ${ARG_TARGET}-as
The issue we observing is that .cl files are compiled sequentially. We don't see problem with .ll file, so we can leave it as-is.

https://github.com/llvm/llvm-project/pull/130755