HPFS: Move declaration up, so that there are no out-of-scope pointers

Move declaration up, so that there are no out-of-scope pointers

Reported-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>