MIPS optimizations for Signal Processing Library patch01

Review URL: https://webrtc-codereview.appspot.com/1028004
Patch from Ljubomir Papuga <lpapuga@mips.com>.

git-svn-id: http://webrtc.googlecode.com/svn/trunk@3557 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/common_audio/signal_processing/signal_processing.gypi

@@ -84,6 +84,12 @@
             }],
           ],
         }],
+        ['target_arch=="mipsel"', {
+          'sources': [
+            'min_max_operations_mips.c',
+            'resample_by_2_mips.c',
+          ],
+        }],
       ],
       # Ignore warning on shift operator promotion.
       'msvs_disabled_warnings': [ 4334, ],