macintosh/windfarm_smu_sat: Fix debug output

There's some antiquated debug output that's trying
to do a hand-made hexdump and turning into horrible
1-byte-per-line output these days.

Use print_hex_dump() instead

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>