cosmetic: rename mgcp_ep.c/h to mgcp_endp.c/h

The short term of endpoint has always been "endp" througout the whole
project and not "ep".

- rename mcgp_ep.c to mgcp_endp.c

- rename mgcp_ep.h to mgcp_endp.h

Change-Id: Id52047bb2d0407655ac272c858ed3412b8ae9e6d
diff --git a/src/libosmo-mgcp/mgcp_osmux.c b/src/libosmo-mgcp/mgcp_osmux.c
index 1bb7aa6..1d3cab3 100644
--- a/src/libosmo-mgcp/mgcp_osmux.c
+++ b/src/libosmo-mgcp/mgcp_osmux.c
@@ -24,7 +24,7 @@
 #include <osmocom/mgcp/mgcp_internal.h>
 #include <osmocom/mgcp/osmux.h>
 #include <osmocom/mgcp/mgcp_conn.h>
-#include <osmocom/mgcp/mgcp_ep.h>
+#include <osmocom/mgcp/mgcp_endp.h>
 
 static struct osmo_fd osmux_fd;