[llvm] [libc] [libc][NFC] Remove __support/bit.h and use __support/CPP/bit.h instead (PR #73939)

[Guillaume Chatelet via llvm-commits]

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@@ -152,9 +152,9 @@ class HashState {
     }
   }
   LIBC_INLINE uint64_t finish() {
-    uint64_t rot = buffer & 63;
+    int rot = buffer & 63;
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gchatelet wrote:

FYI @SchrodingerZhu I had to change the type here to suppress a warning about loss of precision.

https://github.com/llvm/llvm-project/pull/73939