define SELINUX_TRANS_DIR in selinux.h

I wanted to separate this directory out in order for a new patch to mcstransd to watch
this directory for newly created files, which it could then translate.

The idea is libvirt would write to /var/run/setrans/c0:c1,c2 with the contents of vm1, then
setrans could translate the processes to show system_u:system_r:svirt_t:vm1
diff --git a/libselinux/include/selinux/selinux.h b/libselinux/include/selinux/selinux.h
index bffa1f9..66437cd 100644
--- a/libselinux/include/selinux/selinux.h
+++ b/libselinux/include/selinux/selinux.h
@@ -177,6 +177,7 @@
 #define SELINUX_WARNING		1
 #define SELINUX_INFO		2
 #define SELINUX_AVC		3
+#define SELINUX_TRANS_DIR	"/var/run/setrans"
 
 /* Compute an access decision. */
 extern int security_compute_av(const security_context_t scon,
diff --git a/libselinux/src/setrans_internal.h b/libselinux/src/setrans_internal.h
index a801ee8..b3bdca2 100644
--- a/libselinux/src/setrans_internal.h
+++ b/libselinux/src/setrans_internal.h
@@ -1,6 +1,7 @@
 /* Author: Trusted Computer Solutions, Inc. */
+#include <selinux/selinux.h>
 
-#define SETRANS_UNIX_SOCKET "/var/run/setrans/.setrans-unix"
+#define SETRANS_UNIX_SOCKET SELINUX_TRANS_DIR "/.setrans-unix"
 
 #define RAW_TO_TRANS_CONTEXT		2
 #define TRANS_TO_RAW_CONTEXT		3