fs/ntfs3: Add NULL ptr dereference checking at the end of attr_allocate_frame()

[ Upstream commit aaab47f2 ]

It is preferable to exit through the out: label because
internal debugging functions are located there.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>