dt-bindings: mmc: Fix node name in an example

The $nodename allows only "mmc@*" whereas the example node is named
"sdhci".

Signed-off-by: Lubomir Rintel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Ulf Hansson <[email protected]>

Author: lkundrak

Documentation/devicetree/bindings/mmc/mmc-controller.yaml

@@ -351,7 +351,7 @@ dependencies:
 
 examples:
   - |
-    sdhci@ab000000 {
+    mmc@ab000000 {
         compatible = "sdhci";
         reg = <0xab000000 0x200>;
         interrupts = <23>;