Looper - Updated Frip Decay value to use explicit value instead of si…

…n constexpr (electro-smith#170)

* fixes electro-smith#169 - change constant value for frip decay from std::sin to fixed value.

* style fix.

Co-authored-by: stephenhensley <stephen.p.hensley@gmail.com>

Source/Utility/looper.h

@@ -223,7 +223,9 @@ class Looper
 
   private:
     /** Constants */
-    static constexpr float kFripDecayVal      = std::sin(PI_F / 4.f);
+
+    /** Decay value for frippertronics mode is sin(PI / 4) */
+    static constexpr float kFripDecayVal      = 0.7071067811865476f;
     static constexpr int   kNumModes          = 4;
     static constexpr int   kNumPlaybackSpeeds = 3;
     static constexpr int   kWindowSamps       = 1200;