Readme fix: argsort does not use SIMD for 16-bit

Author: sterrettm2

README.md

@@ -58,8 +58,9 @@ data types.
 std::vector<size_t> arg = x86simdsort::argsort(T* arr, size_t size, bool hasnan, bool descending);
 std::vector<size_t> arg = x86simdsort::argselect(T* arr, size_t k, size_t size, bool hasnan);
 ```
-Supported datatypes: `T` $\in$ `[_Float16, uint16_t, int16_t, float, uint32_t,
-int32_t, double, uint64_t, int64_t]`
+Supported datatypes: `T` $\in$ `[_Float16, uint16_t, int16_t, float, uint32_t, int32_t, double,
+uint64_t, int64_t]` Note that argsort and argselect are not accelerated with SIMD when using 16-bit
+data types.
 
 ## Build/Install