misc: Fix compilation now that the method is located in libosmocore

These TLV helper functions are now located in libosmocore.
diff --git a/openbsc/configure.ac b/openbsc/configure.ac
index b56254c..1bb660f 100644
--- a/openbsc/configure.ac
+++ b/openbsc/configure.ac
@@ -53,7 +53,7 @@
 AM_CONDITIONAL(BUILD_SMPP, test "x$osmo_ac_build_smpp" = "xyes")
 
 
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.3.2)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.5.3.60)
 PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 0.3.0)
 PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 0.3.0)
 PKG_CHECK_MODULES(LIBOSMOABIS, libosmoabis >= 0.1.0)
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index 69dde3d..b99c455 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -39,13 +39,6 @@
 #include <openbsc/debug.h>
 #include <openbsc/gb_proxy.h>
 
-static uint16_t tlvp_val16_unal(const struct tlv_parsed *tp, int pos)
-{
-	uint16_t res;
-	memcpy(&res, TLVP_VAL(tp, pos), sizeof(res));
-	return res;
-}
-
 struct gbprox_peer {
 	struct llist_head list;