iOS: Always build H264 HW encoder/decoder

This CL removes the use_objc_h264 flag. This means that the VideoToolbox
H264 encoder and decoder will always be built.

BUG=webrtc:4081
NOTRY=TRUE

Review-Url: https://codereview.webrtc.org/2366443003
Cr-Commit-Position: refs/heads/master@{#14372}

webrtc/modules/video_coding/codecs/h264/h264_objc.mm

@@ -18,8 +18,7 @@
 namespace webrtc {
 
 bool IsH264CodecSupportedObjC() {
-#if defined(WEBRTC_OBJC_H264) && \
-    defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED) && \
+#if defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED) && \
     defined(WEBRTC_IOS)
   // Supported on iOS8+.
   return [[[UIDevice currentDevice] systemVersion] doubleValue] >= 8.0;