f2fs: relocate readdir_ra configure initialization

readdir_ra is sysfs configuration instead of mount option, so it should
not be initialized in default_options(), otherwise after remount, it can
be reset to be enabled which may not as user wish, so let's move it to
f2fs_tuning_parameters().
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/super.c

@@ -1356,7 +1356,6 @@ static void default_options(struct f2fs_sb_info *sbi)
 	F2FS_OPTION(sbi).test_dummy_encryption = false;
 	F2FS_OPTION(sbi).s_resuid = make_kuid(&init_user_ns, F2FS_DEF_RESUID);
 	F2FS_OPTION(sbi).s_resgid = make_kgid(&init_user_ns, F2FS_DEF_RESGID);
-	sbi->readdir_ra = 1;
 
 	set_opt(sbi, BG_GC);
 	set_opt(sbi, INLINE_XATTR);
@@ -2650,6 +2649,8 @@ static void f2fs_tuning_parameters(struct f2fs_sb_info *sbi)
 		sm_i->dcc_info->discard_granularity = 1;
 		sm_i->ipu_policy = 1 << F2FS_IPU_FORCE;
 	}
+
+	sbi->readdir_ra = 1;
 }
 
 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)