spi/pl022: use more managed resources

This switches the PL022 SPI driver to use devm_* managed resources
for IRQ, clocks, ioremap and GPIO. Prior to this, the GPIOs would
even leak.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>