spi/pl022: get/put resources on suspend/resume

This factors out the resource handling in runtime
suspend/resume and also calls it from the ordinary suspend
and resume hooks.

The semantics require that ordinary PM op suspend is called
with runtime PM in resumed mode, so that ordinary suspend
can assume that it will e.g. decrease the clock reference
counter to 0, runtime resume having previously increased it
to 1.

Cc: Vipul Kumar Samar <vipulkumar.samar@st.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>