ARM: dts: zynq: add QSPI controller node

The driver and binding for the Zynq QSPI is already present in the
kernel. The node is not added to the zynq-7000.dtsi, however.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Link: https://lore.kernel.org/r/20220811092036.3689983-1-s.trumtrar@pengutronix.de


Signed-off-by: Michal Simek <michal.simek@amd.com>