fix build warnings in HR implementation

src/components/ble/HeartRateService.cpp

@@ -57,9 +57,7 @@ void HeartRateService::Init() {
 int HeartRateService::OnHeartRateRequested(uint16_t connectionHandle, uint16_t attributeHandle,
                                            ble_gatt_access_ctxt *context) {
   if(attributeHandle == heartRateMeasurementHandle) {
-    NRF_LOG_INFO("BATTERY : handle = %d", heartRateMeasurementHandle);
-    static uint8_t batteryValue = heartRateController.HeartRate();
-
+    NRF_LOG_INFO("HEARTRATE : handle = %d", heartRateMeasurementHandle);
     uint8_t buffer[2] = {0, heartRateController.HeartRate()}; // [0] = flags, [1] = hr value
 
     int res = os_mbuf_append(context->om, buffer, 2);

src/components/ble/NimbleController.cpp

@@ -38,8 +38,8 @@ NimbleController::NimbleController(Pinetime::System::SystemTask& systemTask,
         navService{systemTask},
         batteryInformationService{batteryController},
         immediateAlertService{systemTask, notificationManager},
-        serviceDiscovery({&currentTimeClient, &alertNotificationClient}),
-        heartRateService{systemTask, heartRateController} {
+        heartRateService{systemTask, heartRateController},
+        serviceDiscovery({&currentTimeClient, &alertNotificationClient}) {
 }
 
 int GAPEventCallback(struct ble_gap_event *event, void *arg) {

src/components/heartrate/Ppg.cpp

@@ -13,7 +13,7 @@ using namespace Pinetime::Controllers;
 namespace {
   int Compare(int* d1, int* d2, size_t count) {
     int e = 0;
-    for(int i = 0; i < count; i++) {
+    for(size_t i = 0; i < count; i++) {
       auto d = d1[i] - d2[i];
       e += d * d;
     }

src/drivers/Hrs3300.cpp

@@ -73,11 +73,11 @@ void Hrs3300::SetGain(uint8_t gain) {
   static constexpr uint8_t maxGain = 64;
   gain = std::min(gain, maxGain);
   uint8_t hgain = 0;
-  while((1 << hgain) < gain)
+  while((1 << hgain) < gain) {
     hgain++;
-
     WriteRegister(static_cast<uint8_t>(Registers::Hgain), hgain << 2);
   }
+}
 
 void Hrs3300::SetDrive(uint8_t drive) {
   auto en = ReadRegister(static_cast<uint8_t>(Registers::Enable));