post proc: volume listener: remove unecessary warning log

Remove warning logged in vol_effect_process() in a legitimate
situation where input and output buffer are the same.

Change-Id: Icce8e22d7d78b7577bac5a1a443e1b0527b33899
diff --git a/post_proc/volume_listener.c b/post_proc/volume_listener.c
index ef63299..107a475 100644
--- a/post_proc/volume_listener.c
+++ b/post_proc/volume_listener.c
@@ -346,9 +346,6 @@
             memcpy(out_buffer->raw, in_buffer->raw, out_buffer->frameCount * 2 * sizeof(int16_t));
         }
 
-    } else {
-        ALOGW("%s: something wrong, didn't handle in_buffer and out_buffer same address case",
-              __func__);
     }
 
 exit: