split_util: rename `usbIsActive` to `usb_bus_detected` (#23657)

split_util: rename usbIsActive to usb_bus_detected

This follows the style rules and better reflects the intent.

Signed-off-by: Stefan Kerkmann <karlk90@pm.me>

quantum/split_common/split_util.c

@@ -63,7 +63,7 @@ static struct {
 
 #if defined(SPLIT_USB_DETECT)
 _Static_assert((SPLIT_USB_TIMEOUT / SPLIT_USB_TIMEOUT_POLL) <= UINT16_MAX, "Please lower SPLIT_USB_TIMEOUT and/or increase SPLIT_USB_TIMEOUT_POLL.");
-static bool usbIsActive(void) {
+static bool usb_bus_detected(void) {
     for (uint16_t i = 0; i < (SPLIT_USB_TIMEOUT / SPLIT_USB_TIMEOUT_POLL); i++) {
         // This will return true if a USB connection has been established
         if (usb_connected_state()) {
@@ -74,7 +74,7 @@ static bool usbIsActive(void) {
     return false;
 }
 #else
-static inline bool usbIsActive(void) {
+static inline bool usb_bus_detected(void) {
     return usb_vbus_state();
 }
 #endif
@@ -179,7 +179,7 @@ __attribute__((weak)) bool is_keyboard_left_impl(void) {
 }
 
 __attribute__((weak)) bool is_keyboard_master_impl(void) {
-    bool is_master = usbIsActive();
+    bool is_master = usb_bus_detected();
 
     // Avoid NO_USB_STARTUP_CHECK - Disable USB as the previous checks seem to enable it somehow
     if (!is_master) {