fs/ntfs3: Remove tmp pointer bd_inode in fill_super

Drop tmp pointer bd_inode because this is only used ones in fill_super.
Also we have so many initializing happening at the beginning that it is
already way too much to follow.

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>