core/conv: update description headers for conv_acc_*

Change-Id: I00154776c8e7d346abcbaf9048ce04d9488bb458
diff --git a/src/conv_acc_sse_avx.c b/src/conv_acc_sse_avx.c
index 5d9a82b..2ad353a 100644
--- a/src/conv_acc_sse_avx.c
+++ b/src/conv_acc_sse_avx.c
@@ -1,5 +1,6 @@
 /*
- * Intel SSE + AVX Viterbi decoder
+ * Accelerated Viterbi decoder implementation
+ * for architectures with both SSE3 and AVX2 support
  *
  * Copyright (C) 2013, 2014 Thomas Tsou <tom@tsou.cc>
  *