Remove simd_rem intrinsic definition

It is unused

Author: bjorn3

crates/core_arch/src/simd_llvm.rs

@@ -27,7 +27,6 @@ extern "platform-intrinsic" {
     pub fn simd_sub<T>(x: T, y: T) -> T;
     pub fn simd_mul<T>(x: T, y: T) -> T;
     pub fn simd_div<T>(x: T, y: T) -> T;
-    pub fn simd_rem<T>(x: T, y: T) -> T;
     pub fn simd_shl<T>(x: T, y: T) -> T;
     pub fn simd_shr<T>(x: T, y: T) -> T;
     pub fn simd_and<T>(x: T, y: T) -> T;