[libc] [llvm] [libc][c11] Add stdio.h's rename() function (PR #85068)

[Michael Jones via llvm-commits]

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@@ -355,6 +355,23 @@ if(${LIBC_TARGET_OS} STREQUAL "linux")
   )
 endif()
 
+if(${LIBC_TARGET_OS} STREQUAL "linux")
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michaelrj-google wrote:

this can share a condition with the above test

https://github.com/llvm/llvm-project/pull/85068