staging: erofs: fix a missing endian conversion

[ Upstream commit 37ec35a6cc2b99eb7fd6b85b7d7b75dff46bc353 ]

This patch fixes a missing endian conversion in
vle_get_logical_extent_head.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>