In preparation for allowing QE to be built for architectures other
than ppc, use the generic readx_poll_timeout_atomic() helper from
iopoll.h rather than the ppc-only spin_event_timeout().
Reviewed-by: Timur Tabi <timur@kernel.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Li Yang <leoyang.li@nxp.com>