[libvirt] [PATCH] Fix another printf("%s", NULL) case

[john levon sun com]

# HG changeset patch
# User john levon sun com
# Date 1233199841 28800
# Node ID 3f2af372963ddbae509bd0d1b2e7bdf3ebb4f217
# Parent  76d670ab6ea5476be96441ea88af94644c985201
Fix another printf("%s", NULL) case

Signed-off-by: John Levon <john levon sun com>

diff --git a/src/libvirt.c b/src/libvirt.c
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -6922,7 +6922,7 @@ int
 int
 virNodeNumOfDevices(virConnectPtr conn, const char *cap, unsigned int flags)
 {
-    DEBUG("conn=%p, cap=%s, flags=%d", conn, cap, flags);
+    DEBUG("conn=%p, cap=%s, flags=%d", conn, NULLSTR(cap), flags);
 
     virResetLastError();