fix non-randomness of TMSI by seeding the PRNG.  Later we should use openssl

diff --git a/src/bsc_hack.c b/src/bsc_hack.c
index a76e290..c99159c 100644
--- a/src/bsc_hack.c
+++ b/src/bsc_hack.c
@@ -1076,6 +1076,9 @@
 	}
 	printf("DB: Database prepared.\n");
 
+	/* seed the PRNG */
+	srand(time(NULL));
+
 	rc = bootstrap_network();
 	if (rc < 0)
 		exit(1);