clang compiler warnings: Fix -Wunused-function

This patch fixes clang compilers warnings for unused functions. Specifically:
 * channels/chan_iax2: removed user_ref function
 * main/dsp.c: removed goertzel_update function

Review: https://reviewboard.asterisk.org/r/4527

ASTERISK-24917
Reported by: dkdegroot
patches:
  rb4527.patch submitted by dkdegroot (License 6600)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@433678 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_iax2.c

@@ -1939,11 +1939,6 @@ static struct iax2_user *find_user(const char *name)
 {
 	return ao2_find(users, name, OBJ_KEY);
 }
-static inline struct iax2_user *user_ref(struct iax2_user *user)
-{
-	ao2_ref(user, +1);
-	return user;
-}
 
 static inline struct iax2_user *user_unref(struct iax2_user *user)
 {

main/dsp.c

@@ -330,16 +330,6 @@ static inline void goertzel_sample(goertzel_state_t *s, short sample)
 	}
 }
 
-static inline void goertzel_update(goertzel_state_t *s, short *samps, int count)
-{
-	int i;
-
-	for (i = 0; i < count; i++) {
-		goertzel_sample(s, samps[i]);
-	}
-}
-
-
 static inline float goertzel_result(goertzel_state_t *s)
 {
 	goertzel_result_t r;