Replace C identifier lists with (void) (#809)

These changes were generated by wpilibsuite/styleguide#106.

hal/src/main/native/athena/Accelerometer.cpp

@@ -219,7 +219,7 @@ void HAL_SetAccelerometerRange(HAL_AccelerometerRange range) {
  *
  * This is a floating point value in units of 1 g-force
  */
-double HAL_GetAccelerometerX() {
+double HAL_GetAccelerometerX(void) {
   initializeAccelerometer();
 
   int32_t raw =
@@ -232,7 +232,7 @@ double HAL_GetAccelerometerX() {
  *
  * This is a floating point value in units of 1 g-force
  */
-double HAL_GetAccelerometerY() {
+double HAL_GetAccelerometerY(void) {
   initializeAccelerometer();
 
   int32_t raw =
@@ -245,7 +245,7 @@ double HAL_GetAccelerometerY() {
  *
  * This is a floating point value in units of 1 g-force
  */
-double HAL_GetAccelerometerZ() {
+double HAL_GetAccelerometerZ(void) {
   initializeAccelerometer();
 
   int32_t raw =

hal/src/main/native/athena/HAL.cpp

@@ -177,7 +177,7 @@ const char* HAL_GetErrorMessage(int32_t code) {
 /**
  * Returns the runtime type of this HAL
  */
-HAL_RuntimeType HAL_GetRuntimeType() { return HAL_Athena; }
+HAL_RuntimeType HAL_GetRuntimeType(void) { return HAL_Athena; }
 
 /**
  * Return the FPGA Version number.
@@ -388,8 +388,8 @@ int64_t HAL_Report(int32_t resource, int32_t instanceNumber, int32_t context,
 
 // TODO: HACKS
 // No need for header definitions, as we should not run from user code.
-void NumericArrayResize() {}
-void RTSetCleanupProc() {}
-void EDVR_CreateReference() {}
+void NumericArrayResize(void) {}
+void RTSetCleanupProc(void) {}
+void EDVR_CreateReference(void) {}
 
 }  // extern "C"

hal/src/main/native/athena/SPI.cpp

@@ -98,7 +98,7 @@ static void CommonSPIPortInit(int32_t* status) {
   }
 }
 
-static void CommonSPIPortFree() {
+static void CommonSPIPortFree(void) {
   if (spiPortCount.fetch_sub(1) == 1) {
     // Clean up SPI Handles
     HAL_FreeDIOPort(digitalHandles[3]);