[compiler-rt] [RISCV][compiler-rt] Small fixes for __riscv_feature_bits (PR #99958)

[Kito Cheng via llvm-commits]

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@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "cpu_model.h"
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kito-cheng wrote:

+1 for option 1

https://github.com/llvm/llvm-project/pull/99958