endpoint_t in syslib

- headers use the endpoint_t in syslib.h and the implmentation was using int
  instead. Both uses endpoint_t now

- every variable named like proc, proc_nr or proc_nr_e of type endpoint_t has
  name proc_ep now

- endpoint_t defined as u32_t not int

lib/syslib/sys_trace.c

@@ -1,13 +1,14 @@
 #include "syslib.h"
 
-PUBLIC int sys_trace(req, proc_nr, addr, data_p)
-int req, proc_nr;
+PUBLIC int sys_trace(req, proc_ep, addr, data_p)
+int req;
+endpoint_t proc_ep;
 long addr, *data_p;
 {
   message m;
   int r;
 
-  m.CTL_ENDPT = proc_nr;
+  m.CTL_ENDPT = proc_ep;
   m.CTL_REQUEST = req;
   m.CTL_ADDRESS = addr;
   if (data_p) m.CTL_DATA = *data_p;