ARM: socfpga: dts: fix spi1 interrupt

The socfpga.dtsi currently has the wrong interrupt number set for SPI master 1
Trying to use the master without this change results in the kernel boot
process waiting forever for an interrupt that will never occur while
attempting to probe any slave devices configured in the device tree as being
under SPI master 1.

The change works for the Cyclone V, and according to the Arria 5 handbook
should be good there too.

Signed-off-by: Mark James <maj@jamers.net>
Acked-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>