mgcp: remove unused callback pointer

struct mgcp_config contains a function pointer realloc_cb, which is
never popoulated nor used anywhere in the code. Lets remove it

Change-Id: I8d58281e1ff898638293c9e8cb000329462c7a70
diff --git a/TODO-RELEASE b/TODO-RELEASE
index c5a3b36..741ab14 100644
--- a/TODO-RELEASE
+++ b/TODO-RELEASE
@@ -24,3 +24,4 @@
 # If any interfaces have been removed or changed since the last public release, a=0.
 #
 #library		what		description / commit summary line
+libsomo-mgcp		ABI change	mgcp.h, struct mgcp_config, remove realloc_cb (unused)
\ No newline at end of file
diff --git a/include/osmocom/mgcp/mgcp.h b/include/osmocom/mgcp/mgcp.h
index 43f480e..8cdff59 100644
--- a/include/osmocom/mgcp/mgcp.h
+++ b/include/osmocom/mgcp/mgcp.h
@@ -59,7 +59,6 @@
 #define MGCP_POLICY_REJECT	5
 #define MGCP_POLICY_DEFER	6
 
-typedef int (*mgcp_realloc)(struct mgcp_trunk_config *cfg, int endpoint);
 typedef int (*mgcp_change)(struct mgcp_trunk_config *cfg, int endpoint, int state);
 typedef int (*mgcp_policy)(struct mgcp_trunk_config *cfg, int endpoint, int state, const char *transactio_id);
 typedef int (*mgcp_reset)(struct mgcp_trunk_config *cfg);
@@ -256,7 +255,6 @@
 	mgcp_change change_cb;
 	mgcp_policy policy_cb;
 	mgcp_reset reset_cb;
-	mgcp_realloc realloc_cb;
 	mgcp_rqnt rqnt_cb;
 	void *data;