f2fs: inject page allocation failures

This patch adds page allocation failures.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 9a56f54..986d0da 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -45,6 +45,7 @@
 
 char *fault_name[FAULT_MAX] = {
 	[FAULT_KMALLOC]		= "kmalloc",
+	[FAULT_PAGE_ALLOC]	= "page alloc",
 };
 #endif