Revert of Code's more readable when SkPMFloat is an Sk4f.

src/opts/SkNx_neon.h

Index: src/opts/SkNx_neon.h
diff --git a/src/opts/SkNx_neon.h b/src/opts/SkNx_neon.h
index 451482936fcd8d6d5fe2476f7fa6331cb4d9dae8..c8580bca5a4a0fd23b7e6baf4bf7cdf0a0db7c0c 100644
--- a/src/opts/SkNx_neon.h
+++ b/src/opts/SkNx_neon.h
@@ -187,6 +187,7 @@
     typedef SkNi<4, int32_t> Ni;
 public:
     SkNf(float32x4_t vec) : fVec(vec) {}
+    float32x4_t vec() const { return fVec; }
 
     SkNf() {}
     explicit SkNf(float val)           : fVec(vdupq_n_f32(val)) {}
@@ -251,7 +252,7 @@
         return vgetq_lane_f32(fVec, k&3);
     }
 
-protected:
+private:
     float32x4_t fVec;
 };