nvmem: dt-bindings: Fix the error of dt-bindings check

1. Remove the unnecessary header file for dt-binding check
2. Replace OTPRX with 0x15 since it is not defined here.
3. Modify the name of the node of the clock driver.

Fixes: 8fb29b45 ("dt-bindings: nvmem: Add bindings doc for Sunplus OCOTP driver")
Reported-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Vincent Shih <vincent.sunplus@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220225175822.8293-2-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/nvmem/sunplus,sp7021-ocotp.yaml

@@ -60,13 +60,11 @@ unevaluatedProperties: false
 
 examples:
   - |
-    #include <dt-bindings/clock/sp-sp7021.h>
-
     otp: otp@9c00af00 {
         compatible = "sunplus,sp7021-ocotp";
         reg = <0x9c00af00 0x34>, <0x9c00af80 0x58>;
         reg-names = "hb_gpio", "otprx";
-        clocks = <&clks OTPRX>;
+        clocks = <&clkc 0x15>;
 
         #address-cells = <1>;
         #size-cells = <1>;