tests: fix bsc-nat test

In 136f453dd2492b95004461a33c90b11732f33bd8, I forgot to update
the new header path in the test/bsc-nat files (this happened to
me because I forgot to configured openBSC without --enable-nat).
diff --git a/openbsc/tests/bsc-nat/bsc_nat_test.c b/openbsc/tests/bsc-nat/bsc_nat_test.c
index 504b691..f5de953 100644
--- a/openbsc/tests/bsc-nat/bsc_nat_test.c
+++ b/openbsc/tests/bsc-nat/bsc_nat_test.c
@@ -27,10 +27,10 @@
 #include <openbsc/bsc_nat.h>
 #include <openbsc/bsc_nat_sccp.h>
 
-#include <osmocore/talloc.h>
+#include <osmocom/core/talloc.h>
 
 #include <osmocom/sccp/sccp.h>
-#include <osmocore/protocol/gsm_08_08.h>
+#include <osmocom/gsm/protocol/gsm_08_08.h>
 
 #include <stdio.h>