Reformat existing code. There should be no functional effects.

webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S

 @
 @ Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 @
 @ Use of this source code is governed by a BSD-style license
 @ that can be found in the LICENSE file in the root of the source
 @ tree. An additional intellectual property rights grant can be found
 @ in the file PATENTS.  All contributing project authors may
 @ be found in the AUTHORS file in the root of the source tree.
 @
 
@@ skipping 142 matching lines @@
 @Reference C code:
 @
 @void WebRtcSpl_FilterARFastQ12(int16_t* data_in,
 @                               int16_t* data_out,
 @                               int16_t* __restrict coefficients,
 @                               int coefficients_length,
 @                               int data_length) {
 @  int i = 0;
 @  int j = 0;
 @
+@  assert(data_length > 0);
+@  assert(coefficients_length > 1);
+@
 @  for (i = 0; i < data_length - 1; i += 2) {
 @    int32_t output1 = 0;
 @    int32_t sum1 = 0;
 @    int32_t output2 = 0;
 @    int32_t sum2 = 0;
 @
 @    for (j = coefficients_length - 1; j > 2; j -= 2) {
 @      sum1 += coefficients[j]      * data_out[i - j];
 @      sum1 += coefficients[j - 1]  * data_out[i - j + 1];
 @      sum2 += coefficients[j]     * data_out[i - j + 1];
@@ skipping 33 matching lines @@
 @      sum1 += coefficients[1] * data_out[i - 1];
 @    }
 @
 @    output1 = coefficients[0] * data_in[i];
 @    output1 -= sum1;
 @    // Saturate and store the output.
 @    output1 = WEBRTC_SPL_SAT(134215679, output1, -134217728);
 @    data_out[i] = (int16_t)((output1 + 2048) >> 12);
 @  }
 @}