Some minor example promotion cleanup

Author: earlephilhower

libraries/BluetoothHIDMaster/examples/KeyboardPiano/KeyboardPiano.ino

@@ -91,7 +91,7 @@ void mb(void *cbdata, int butt, bool down) {
 inline uint32_t stepForHz(float hz) {
   const float stepHz = 1000.0 / 44100.0;
   const float step = hz * stepHz;
-  return (uint32_t)(step * 65536.0);
+  return (uint32_t)(step * 65536.0f);
 }
 
 uint32_t keyStepMap[128]; // The frequency of any raw HID key

libraries/Mouse/examples/Circle/Circle.ino

@@ -17,7 +17,7 @@ void loop() {
     float r = 100;
     float ox = 0.0;
     float oy = 0.0;
-    for (float a = 0; a < 2.0 * 3.14159; a += 0.1) {
+    for (float a = 0.0f; a < 2.0f * 3.14159f; a += 0.1f) {
       float ax = r * cos(a);
       float ay = r * sin(a);
       float dx = ax - ox;

libraries/MouseAbsolute/examples/CircleAbsolute/CircleAbsolute.ino

@@ -17,7 +17,7 @@ void loop() {
     float r = 1000;
     for (float cx = 1000; cx <= 16000; cx += 4000) {
       for (float cy = 1000; cy <= 16000; cy += 4000) {
-        for (float a = 0; a < 2.0 * 3.14159; a += 0.1) {
+        for (float a = 0.0f; a < 2.0f * 3.14159f; a += 0.1f) {
           float ax = r * cos(a);
           float ay = r * sin(a);
           MouseAbsolute.move(ax + cx, ay + cy, 0);