fix: change function signature of v128.pmin and v128.pmax

Author: chen ruixiang

NOTICE

@@ -49,6 +49,7 @@ under the licensing terms detailed in LICENSE:
 * Peter Hayman <peteyhayman@gmail.com>
 * ApsarasX <apsarax@outlook.com>
 * Adrien Zinger <zinger.ad@gmail.com>
+* Ruixiang Chen <xiang19890319@gmail.com>
 
 Portions of this software are derived from third-party works licensed under
 the following terms:

std/assembly/index.d.ts

@@ -842,9 +842,9 @@ declare namespace v128 {
   /** Computes the maximum of each lane. */
   export function max<T>(a: v128, b: v128): v128;
   /** Computes the pseudo-minimum of each lane. */
-  export function pmin<T>(a: v128, b: v128): v128;
+  export function pmin<T extends f32 | f64>(a: v128, b: v128): v128;
   /** Computes the pseudo-maximum of each lane. */
-  export function pmax<T>(a: v128, b: v128): v128;
+  export function pmax<T extends f32 | f64>(a: v128, b: v128): v128;
   /** Computes the dot product of two lanes each, yielding lanes one size wider than the input. */
   export function dot<T extends i16>(a: v128, b: v128): v128;
   /** Computes the average of each lane. */