mme: link against gnutls

Fix for:
/usr/bin/ld: key_derivation.so: undefined reference to `gnutls_hmac_fast'

Related: OS#5252
Change-Id: Iacddc22ecda187e250db9cfb1ca1d1d341ce78f4
diff --git a/mme/regen_makefile.sh b/mme/regen_makefile.sh
index 8106664..5606879 100755
--- a/mme/regen_makefile.sh
+++ b/mme/regen_makefile.sh
@@ -26,4 +26,4 @@
 
 ../regen-makefile.sh MME_Tests.ttcn $FILES
 
-sed -i -e 's/^LINUX_LIBS = -lxml2 -lsctp/LINUX_LIBS = -lxml2 -lsctp -lfftranscode/' Makefile
+sed -i -e 's/^LINUX_LIBS = -lxml2 -lsctp/LINUX_LIBS = -lxml2 -lsctp -lfftranscode -lgnutls/' Makefile