[compiler-rt] [compiler-rt] Propagate sysroot from CMake to msan tests (PR #132299)

[Petr Hosek via llvm-commits]

================
@@ -63,7 +63,11 @@ set(MSAN_UNITTEST_LINK_FLAGS
   # inputs.
 )
 
-append_list_if(COMPILER_RT_HAS_LIBDL -ldl MSAN_UNITTEST_LINK_FLAGS)
+if (LINUX)
+  append_list_if(CMAKE_SYSROOT "--sysroot=${CMAKE_SYSROOT}" MSAN_UNITTEST_LINK_FLAGS)
+endif()
+
+  append_list_if(COMPILER_RT_HAS_LIBDL -ldl MSAN_UNITTEST_LINK_FLAGS)
----------------
petrhosek wrote:

```suggestion
append_list_if(COMPILER_RT_HAS_LIBDL -ldl MSAN_UNITTEST_LINK_FLAGS)
```

https://github.com/llvm/llvm-project/pull/132299