Fix compile warning in uli526x driver

uli526x.c: In function 'uli526x_init_one':
uli526x.c:314:2: warning: dereferencing type-punned pointer will break strict-aliasing rules
uli526x.c:314:2: warning: dereferencing type-punned pointer will break strict-aliasing rules

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>