f2fs: surround fault_injection related option parsing using CONFIG_F2FS_FAULT_INJECTION

It's a little bit strange when fault_injection related
options fail with -EINVAL which were already disabled
from config, so surround all fault_injection related option
parsing code using CONFIG_F2FS_FAULT_INJECTION. Meanwhile,
slightly change warning message to keep consistency with
option POSIX_ACL and FS_XATTR.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/super.c

@@ -594,28 +594,31 @@ static int parse_options(struct super_block *sb, char *options)
 			}
 			F2FS_OPTION(sbi).write_io_size_bits = arg;
 			break;
+#ifdef CONFIG_F2FS_FAULT_INJECTION
 		case Opt_fault_injection:
 			if (args->from && match_int(args, &arg))
 				return -EINVAL;
-#ifdef CONFIG_F2FS_FAULT_INJECTION
 			f2fs_build_fault_attr(sbi, arg, F2FS_ALL_FAULT_TYPE);
 			set_opt(sbi, FAULT_INJECTION);
-#else
-			f2fs_msg(sb, KERN_INFO,
-				"FAULT_INJECTION was not selected");
-#endif
 			break;
+
 		case Opt_fault_type:
 			if (args->from && match_int(args, &arg))
 				return -EINVAL;
-#ifdef CONFIG_F2FS_FAULT_INJECTION
 			f2fs_build_fault_attr(sbi, 0, arg);
 			set_opt(sbi, FAULT_INJECTION);
+			break;
 #else
+		case Opt_fault_injection:
 			f2fs_msg(sb, KERN_INFO,
-				"FAULT_INJECTION was not selected");
-#endif
+				"fault_injection options not supported");
 			break;
+
+		case Opt_fault_type:
+			f2fs_msg(sb, KERN_INFO,
+				"fault_type options not supported");
+			break;
+#endif
 		case Opt_lazytime:
 			sb->s_flags |= SB_LAZYTIME;
 			break;