Clear 2 unused functions in audio processing aecm module.
Clear 2 unused functions in audio processing aecm module.

unused functions:
WebRtcAecm_WindowAndFFTNeon
WebRtcAecm_InverseFFTAndWindowNeon

BUG=3580
R=andrew@webrtc.org

Change-Id: I12c50a8706d40f9ea98208b5733c00ede7b1f435

Review URL: https://webrtc-codereview.appspot.com/30269004

Patch from Zhongwei Yao <zhongwei.yao@arm.com>.

git-svn-id: 03ae4fbe531b1eefc9d815f31e49022782c42458@7782 4adac7df-926f-26a2-2b94-8c16560cd09d

krieger-od/nwjs_chromium_webrtc,Alkalyne/webrtctrunk,aleonliao/webrtc-trunk,aleonliao/webrtc-trunk,krieger-od/nwjs_chromium_webrtc,sippet/webrtc,PersonifyInc/chromium_webrtc,krieger-od/webrtc,PersonifyInc/chromium_webrtc,krieger-od/nwjs_chromium_webrtc,Alkalyne/webrtctrunk,aleonliao/webrtc-trunk,krieger-od/webrtc,sippet/webrtc,sippet/webrtc,krieger-od/webrtc,Alkalyne/webrtctrunk,jchavanton/webrtc,jchavanton/webrtc,krieger-od/webrtc,krieger-od/webrtc,aleonliao/webrtc-trunk,jchavanton/webrtc,PersonifyInc/chromium_webrtc,sippet/webrtc,Alkalyne/webrtctrunk,PersonifyInc/chromium_webrtc,jchavanton/webrtc,PersonifyInc/chromium_webrtc,Alkalyne/webrtctrunk,krieger-od/nwjs_chromium_webrtc,aleonliao/webrtc-trunk,sippet/webrtc,Alkalyne/webrtctrunk,jchavanton/webrtc,krieger-od/nwjs_chromium_webrtc,krieger-od/webrtc,jchavanton/webrtc,aleonliao/webrtc-trunk,PersonifyInc/chromium_webrtc,jchavanton/webrtc,Alkalyne/webrtctrunk,krieger-od/nwjs_chromium_webrtc,Alkalyne/webrtctrunk,sippet/webrtc