Make inline function compatible for GCC5

opencryptoki-3.2-missing-sources-and-libraries.patch

@@ -197,3 +197,15 @@ diff --git a/usr/lib/pkcs11/tpm_stdll/Makefile.am b/usr/lib/pkcs11/tpm_stdll/Mak
  					      ../common/loadsave.c	\
  					      ../common/utility.c	\
  					      ../common/mech_des.c	\
+diff --git a/usr/lib/pkcs11/common/btree.c b/usr/lib/pkcs11/common/btree.c
+--- a/usr/lib/pkcs11/common/btree.c
++++ b/usr/lib/pkcs11/common/btree.c
+@@ -242,7 +242,7 @@ bt_node_free(struct btree *t, unsigned long node_num, void (*delete_func)(void *
+  *
+  * return 0 if binary tree has at least 1 node in use, !0 otherwise
+  */
+-inline int
++extern inline int
+ bt_is_empty(struct btree *t)
+ {
+ 	return (t->free_nodes == t->size);