[media] gspca: print small buffers via %*ph

Instead of passing each byte through stack let's use %*ph specifier to do this
job better.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>