ARM: dts: 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.

Fixes: 26ca8b52d6e1 ("ARM: dts: add support for Turris Omnia")
Signed-off-by: Marek Behún <[e-mail]>
Signed-off-by: Gregory CLEMENT <[e-mail]>

arch/arm/boot/dts/armada-385-turris-omnia.dts

···
 		marvell,function = "spi0";
 	};
 
-	spi0cs1_pins: spi0cs1-pins {
+	spi0cs2_pins: spi0cs2-pins {
 		marvell,pins = "mpp26";
 		marvell,function = "spi0";
 	};
···
 		};
 	};
 
-	/* MISO, MOSI, SCLK and CS1 are routed to pin header CN11 */
+	/* MISO, MOSI, SCLK and CS2 are routed to pin header CN11 */
 };
 
 &uart0 {