split off osmo-sgsn: remove files, apply build

Change-Id: I5d27ff93e56cd13e0e70edd15e2080201e35e91f
diff --git a/include/openbsc/gprs_utils.h b/include/openbsc/gprs_utils.h
index 574f5c5..e06364d 100644
--- a/include/openbsc/gprs_utils.h
+++ b/include/openbsc/gprs_utils.h
@@ -24,6 +24,8 @@
 #include <stdint.h>
 #include <sys/types.h>
 
+#include <osmocom/core/msgb.h>
+
 struct msgb;
 struct gprs_ra_id;
 
@@ -42,3 +44,12 @@
 void gprs_parse_tmsi(const uint8_t *value, uint32_t *tmsi);
 
 int gprs_ra_id_equals(const struct gprs_ra_id *id1, const struct gprs_ra_id *id2);
+
+#define GSM48_ALLOC_SIZE        2048
+#define GSM48_ALLOC_HEADROOM    256
+
+static inline struct msgb *gsm48_msgb_alloc_name(const char *name)
+{
+        return msgb_alloc_headroom(GSM48_ALLOC_SIZE, GSM48_ALLOC_HEADROOM,
+                                   name);
+}