ARM: dts: versatile: Update spi clock-names property

Now that spi pl022 binding only accept "sspclk" as clock name, versatile
platform with "SSPCLK" clock name start raising dtbs_check warnings.
Make necessary changes to update this property in order to make it
compliant with binding.

clock-names:0: 'sspclk' was expected
Signed-off-by: Kuldeep Singh <singh.kuldeep87k@gmail.com>
Link: https://lore.kernel.org/r/20220312113853.63446-4-singh.kuldeep87k@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/versatile-ab.dts

@@ -391,7 +391,7 @@ spi@101f4000 {
 			reg = <0x101f4000 0x1000>;
 			interrupts = <11>;
 			clocks = <&xtal24mhz>, <&pclk>;
-			clock-names = "SSPCLK", "apb_pclk";
+			clock-names = "sspclk", "apb_pclk";
 		};
 
 		fpga {