mm/buddy: dump PG_compound_lock page flag

The array pageflag_names[] does conversion from page flags into their
corresponding names so that a meaningful representation of the
corresponding page flag can be printed.  This mechanism is used while
dumping page frames.  However, the array missed PG_compound_lock.  So
the PG_compound_lock page flag would be printed as a digital number
instead of a meaningful string.

The patch fixes that and prints "compound_lock" for the PG_compound_lock
page flag.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -5972,6 +5972,9 @@ static struct trace_print_flags pageflag_names[] = {
 #endif
 #ifdef CONFIG_MEMORY_FAILURE
 	{1UL << PG_hwpoison,		"hwpoison"	},
+#endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	{1UL << PG_compound_lock,	"compound_lock"	},
 #endif
 	{-1UL,				NULL		},
 };