Branch b1_6

b=17199
i=johann, bobijam
Patch provide by LLNL.

Skip dumping log if panic_on_lbug is set.

lnet/libcfs/linux/linux-debug.c

@@ -193,7 +193,8 @@ void lbug_with_loc(const char *file, const char *func, const int line)
         }
 
         libcfs_debug_dumpstack(NULL);
-        libcfs_debug_dumplog();
+        if (!libcfs_panic_on_lbug)
+                libcfs_debug_dumplog();
         libcfs_run_lbug_upcall(file, func, line);
         if (libcfs_panic_on_lbug)
                 panic("LBUG");