av: replace getService with waitForService

- getService is deprecated, following ag/21610323 to remove similar
  pattterns

Test: build
Bug: 284487308
Change-Id: I2a2e90fdcf1e2c1ea025935c3e76eeff6b97fd5f
diff --git a/camera/CameraBase.cpp b/camera/CameraBase.cpp
index 9ae4607..ef40f6c 100644
--- a/camera/CameraBase.cpp
+++ b/camera/CameraBase.cpp
@@ -103,7 +103,6 @@
 
 namespace {
     sp<::android::hardware::ICameraService> gCameraService;
-    const int                 kCameraServicePollDelay = 500000; // 0.5s
     const char*               kCameraServiceName      = "media.camera";
 
     Mutex                     gLock;
@@ -141,14 +140,10 @@
 
         sp<IServiceManager> sm = defaultServiceManager();
         sp<IBinder> binder;
-        do {
-            binder = sm->getService(String16(kCameraServiceName));
-            if (binder != 0) {
-                break;
-            }
-            ALOGW("CameraService not published, waiting...");
-            usleep(kCameraServicePollDelay);
-        } while(true);
+        binder = sm->waitForService(String16(kCameraServiceName));
+        if (binder == nullptr) {
+            return nullptr;
+        }
         if (gDeathNotifier == NULL) {
             gDeathNotifier = new DeathNotifier();
         }