common/math_util: Move contents into the Common namespace

These types are within the common library, so they should be within the
Common namespace.

src/input_common/motion_emu.cpp

@@ -46,7 +46,7 @@ public:
             } else {
                 tilt_direction = mouse_move.Cast<float>();
                 tilt_angle = std::clamp(tilt_direction.Normalize() * sensitivity, 0.0f,
-                                        MathUtil::PI * this->tilt_clamp / 180.0f);
+                                        Common::PI * this->tilt_clamp / 180.0f);
             }
         }
     }
@@ -109,7 +109,7 @@ private:
 
             // Find the angular rate vector in world space
             auto angular_rate = ((q - old_q) * inv_q).xyz * 2;
-            angular_rate *= 1000 / update_millisecond / MathUtil::PI * 180;
+            angular_rate *= 1000 / update_millisecond / Common::PI * 180;
 
             // Transform the two vectors from world space to 3DS space
             gravity = QuaternionRotate(inv_q, gravity);

src/input_common/udp/client.cpp

@@ -217,7 +217,8 @@ void TestCommunication(const std::string& host, u16 port, u8 pad_index, u32 clie
             success_callback();
         else
             failure_callback();
-    }).detach();
+    })
+        .detach();
 }
 
 CalibrationConfigurationJob::CalibrationConfigurationJob(
@@ -268,7 +269,8 @@ CalibrationConfigurationJob::CalibrationConfigurationJob(
         complete_event.Wait();
         socket.Stop();
         worker_thread.join();
-    }).detach();
+    })
+        .detach();
 }
 
 CalibrationConfigurationJob::~CalibrationConfigurationJob() {