arm: mvebu: turris_omnia: Fix mpp26 pin name and comment

There is a bug in Turris Omnia's schematics, whereupon the MPP[26] pin,
which is routed to CN11 pin header, is documented as SPI CS1, but
MPP[26] pin does not support this function. Instead it controls chip
select 2 if in "spi0" mode.

Fix the name of the pin node in pinctrl node and fix the comment in SPI
node.

Signed-off-by: Marek BehĂșn <kabel@kernel.org>
diff --git a/arch/arm/dts/armada-385-turris-omnia.dts b/arch/arm/dts/armada-385-turris-omnia.dts
index 9980a85..0be55f8 100644
--- a/arch/arm/dts/armada-385-turris-omnia.dts
+++ b/arch/arm/dts/armada-385-turris-omnia.dts
@@ -488,7 +488,7 @@
 		marvell,function = "spi0";
 	};
 
-	spi0cs1_pins: spi0cs1-pins {
+	spi0cs2_pins: spi0cs2-pins {
 		marvell,pins = "mpp26";
 		marvell,function = "spi0";
 	};
@@ -523,7 +523,7 @@
 		};
 	};
 
-	/* MISO, MOSI, SCLK and CS1 are routed to pin header CN11 */
+	/* MISO, MOSI, SCLK and CS2 are routed to pin header CN11 */
 };
 
 &uart0 {