GPRS: unify NS state printing

* introduce defines with NS state names
* use them for vty and tests
* expand test output to print complete NS state

Change-Id: I69f8d536135ae76dbca623c2f1ffba625adcb1e9
Related: SYS#3610
diff --git a/include/osmocom/gprs/gprs_ns.h b/include/osmocom/gprs/gprs_ns.h
index d4aef82..2d2f86e 100644
--- a/include/osmocom/gprs/gprs_ns.h
+++ b/include/osmocom/gprs/gprs_ns.h
@@ -43,6 +43,10 @@
 #define NSE_S_ALIVE	0x0002
 #define NSE_S_RESET	0x0004
 
+#define NS_DESC_B(st) ((st) & NSE_S_BLOCKED ? "BLOCKED" : "UNBLOCKED")
+#define NS_DESC_A(st) ((st) & NSE_S_ALIVE ? "ALIVE" : "DEAD")
+#define NS_DESC_R(st) ((st) & NSE_S_RESET ? "RESET" : "UNRESET")
+
 /*! Osmocom NS link layer types */
 enum gprs_ns_ll {
 	GPRS_NS_LL_UDP,		/*!< NS/UDP/IP */