[POWERPC] spufs: fix marker name for find_victim

Fix a typo in the marker for the find_victim function, which prevented
it from being traced. It previously read find_vitim.

Signed-off-by: Julio M. Merino Vidal <jmerino@ac.upc.edu>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>