Fix doc of log function

Author: NaokiM03

library/core/src/num/uint_macros.rs

@@ -688,7 +688,7 @@ macro_rules! uint_impl {
         /// rounded down.
         ///
         /// This method might not be optimized owing to implementation details;
-        /// `log2` can produce results more efficiently for base 2, and `log10`
+        /// `ilog2` can produce results more efficiently for base 2, and `ilog10`
         /// can produce results more efficiently for base 10.
         ///
         /// # Panics