Fix warning while building mediaserver

In file included from frameworks/av/services/audiopolicy/managerdefault/AudioPolicyManager.h:31:0,
                 from frameworks/av/services/audiopolicy/service/AudioPolicyService.h:38,
                 from frameworks/av/media/mediaserver/main_mediaserver.cpp:36:
frameworks/av/services/audiopolicy/managerdefault/ConfigParsingUtils.h:29:0: warning: "ARRAY_SIZE" redefined
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 ^
In file included from frameworks/av/media/libmediaplayerservice/MediaPlayerService.h:31:0,
                 from frameworks/av/media/mediaserver/main_mediaserver.cpp:35:
frameworks/av/include/media/stagefright/foundation/ABase.h:21:0: note: this is the location of the previous definition
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a)))
 ^

Change-Id: I4b80f783c592a78aa88b3dad297278353740466e