hal: add support for all_call_states key

Add support for all_call_states which can be queried by
applications to know call states.

Change-Id: I5ba66186e9d9f6d5769a814f4c1e0627c6f6dd74
diff --git a/hal/voice.c b/hal/voice.c
index cbf8956..32bb8fd 100644
--- a/hal/voice.c
+++ b/hal/voice.c
@@ -351,6 +351,13 @@
     return ret;
 }
 
+void voice_get_parameters(struct audio_device *adev,
+                          struct str_parms *query,
+                          struct str_parms *reply)
+{
+    voice_extn_get_parameters(adev, query, reply);
+}
+
 int voice_set_parameters(struct audio_device *adev, struct str_parms *parms)
 {
     char *str;