fs/ntfs3: Init spi more in init_fs_context than fill_super

init_fs_context() is meant to initialize s_fs_info (spi). Move spi
initializing code there which we can initialize before fill_super().

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