Avoid printf("%s", NULL);

Index: source3/lib/sysquotas.c
--- source3/lib/sysquotas.c.orig
+++ source3/lib/sysquotas.c
@@ -517,10 +517,10 @@ int sys_get_quota(const char *path, enum SMB_QUOTA_TYP
 			ret = sys_quota_backends[i].get_quota(mntpath, bdev, qtype, id, dp);
 			if (ret!=0) {
 				DEBUG(3,("sys_get_%s_quota() failed for mntpath[%s] bdev[%s] qtype[%d] id[%d]: %s.\n",
-					fs,mntpath,bdev,qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid),strerror(errno)));
+					fs,mntpath,bdev?bdev:"(NULL)",qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid),strerror(errno)));
 			} else {
 				DEBUG(10,("sys_get_%s_quota() called for mntpath[%s] bdev[%s] qtype[%d] id[%d].\n",
-					fs,mntpath,bdev,qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid)));
+					fs,mntpath,bdev?bdev:"(NULL)",qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid)));
 			}
 			ready = True;
 			break;	
@@ -532,10 +532,10 @@ int sys_get_quota(const char *path, enum SMB_QUOTA_TYP
 		ret=sys_get_vfs_quota(mntpath, bdev, qtype, id, dp);
 		if (ret!=0) {
 			DEBUG(3,("sys_get_%s_quota() failed for mntpath[%s] bdev[%s] qtype[%d] id[%d]: %s\n",
-				"vfs",mntpath,bdev,qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid),strerror(errno)));
+				"vfs",mntpath,bdev?bdev:"(NULL)",qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid),strerror(errno)));
 		} else {
 			DEBUG(10,("sys_get_%s_quota() called for mntpath[%s] bdev[%s] qtype[%d] id[%d].\n",
-				"vfs",mntpath,bdev,qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid)));
+				"vfs",mntpath,bdev?bdev:"(NULL)",qtype,(qtype==SMB_GROUP_QUOTA_TYPE?id.gid:id.uid)));
 		}
 	}
 
