[libc] [llvm] [libc][NFC] Move float macro into its own header / add target os detection (PR #73311)

[Guillaume Chatelet via llvm-commits]

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@@ -147,6 +147,8 @@ add_header_library(
     type_traits/true_type.h
     type_traits/type_identity.h
     type_traits/void_t.h
+  DEPENDS
+    libc.src.__support.macros.properties.float
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gchatelet wrote:

Thx for noticing I'll fix this in a separate patch.

https://github.com/llvm/llvm-project/pull/73311