dts: synquacer: Drop unused and undocumented SPI properties

'active_clk_edges' and 'chipselect_num' SPI controller properties are
unused in u-boot and Linux. They are also not documented in the binding.
So drop them.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Jassi Brar <jaswinder.singh@linaro.org>
diff --git a/arch/arm/dts/synquacer-sc2a11-developerbox-u-boot.dtsi b/arch/arm/dts/synquacer-sc2a11-developerbox-u-boot.dtsi
index 6b85c05..9f9837b 100644
--- a/arch/arm/dts/synquacer-sc2a11-developerbox-u-boot.dtsi
+++ b/arch/arm/dts/synquacer-sc2a11-developerbox-u-boot.dtsi
@@ -20,8 +20,6 @@
 		#address-cells = <1>;
 		#size-cells = <0>;
 		status = "okay";
-		active_clk_edges;
-		chipselect_num = <1>;
 
 		flash@0 {
 			#address-cells = <1>;