hob: fix rotating progress icon animation

I've always found it somewhat annoying that this icon's rotation
animation wasn't quite correct; this was because it was looping around
to the second position instead of the first, which made it appear to
stutter.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>