dts: cadence_spi: Sync DT bindings with Linux

Adopt the Linux DT bindings and clean-up duplicate
and unused values.

Fix indentation of the QSPI node in the keystone k2g
device tree.

Tested on TI K2G platform:
Tested-by: Vignesh R <vigneshr@ti.com>

Tested on a socfpga-cyclonev board:
Tested-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>

Signed-off-by: Jason Rush <jarush@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Acked-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Marek Vasut <marex@denx.de>
diff --git a/arch/arm/dts/socfpga_arria10.dtsi b/arch/arm/dts/socfpga_arria10.dtsi
index 377700d..abfd0bc 100644
--- a/arch/arm/dts/socfpga_arria10.dtsi
+++ b/arch/arm/dts/socfpga_arria10.dtsi
@@ -734,8 +734,8 @@
 			clocks = <&l4_main_clk>;
 			ext-decoder = <0>;  /* external decoder */
 			num-chipselect = <4>;
-			fifo-depth = <128>;
-			sram-size = <512>;
+			cdns,fifo-depth = <128>;
+			cdns,fifo-width = <4>;
 			bus-num = <2>;
 			status = "disabled";
 		};