Unreviewed changes

2 is the latest approved patch-set.
The change was submitted with unreviewed changes in the following files:

```
The name of the file: src/simd/archsimd/ops_amd64.go
Insertions: 6, Deletions: 6.

@@ -5687,37 +5687,37 @@
 /* Scale */
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPS, CPU Feature: AVX512
 func (x Float32x4) Scale(y Float32x4) Float32x4
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPS, CPU Feature: AVX512
 func (x Float32x8) Scale(y Float32x8) Float32x8
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPS, CPU Feature: AVX512
 func (x Float32x16) Scale(y Float32x16) Float32x16
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPD, CPU Feature: AVX512
 func (x Float64x2) Scale(y Float64x2) Float64x2
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPD, CPU Feature: AVX512
 func (x Float64x4) Scale(y Float64x4) Float64x4
 
 // Scale multiplies each element of x by 2 raised to the power of the
-// corresponding element in y.
+// floor of the corresponding element in y.
 //
 // Asm: VSCALEFPD, CPU Feature: AVX512
 func (x Float64x8) Scale(y Float64x8) Float64x8
```
```
The name of the file: src/simd/archsimd/_gen/simdgen/ops/FPonlyArith/categories.yaml
Insertions: 1, Deletions: 1.

@@ -19,7 +19,7 @@
   commutative: false
   documentation: !string |-
     // NAME multiplies each element of x by 2 raised to the power of the
-    // corresponding element in y.
+    // floor of the corresponding element in y.
 - go: RoundToEven
   commutative: false
   constImm: 0
```

Change information

simd/archsimd: adjust documentations slightly

- Reword the documentation of Scale to mention parameter names.
- Correct the parameter name in Merge.
- Use proper a/an articles in some documentation.
- Add punctuations.
- Format code blocks for long expressions.