dt-bindings: soc: imx8mp-media-blk-ctrl: Fix DT example

The DT example incorrectly names the ISP power domain "isp1" instead of
"isp". This causes a validation failure:

Documentation/devicetree/bindings/soc/imx/fsl,imx8mp-media-blk-ctrl.example.dtb: blk-ctl@32ec0000: power-domain-names:7: 'isp' was expected
        From schema: Documentation/devicetree/bindings/soc/imx/fsl,imx8mp-media-blk-ctrl.yaml

Fix it.

Fixes: 8b3dd27b ("dt-bindings: soc: Add i.MX8MP media block control DT bindings")
Reported-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220510200543.13482-1-laurent.pinchart@ideasonboard.com

Documentation/devicetree/bindings/soc/imx/fsl,imx8mp-media-blk-ctrl.yaml

@@ -88,7 +88,7 @@ examples:
                         <&mediamix_pd>, <&ispdwp_pd>, <&ispdwp_pd>,
                         <&mipi_phy2_pd>;
         power-domain-names = "bus", "mipi-dsi1", "mipi-csi1", "lcdif1", "isi",
-                             "mipi-csi2", "lcdif2", "isp1", "dwe", "mipi-dsi2";
+                             "mipi-csi2", "lcdif2", "isp", "dwe", "mipi-dsi2";
         clocks = <&clk IMX8MP_CLK_MEDIA_APB_ROOT>,
                  <&clk IMX8MP_CLK_MEDIA_AXI_ROOT>,
                  <&clk IMX8MP_CLK_MEDIA_CAM1_PIX_ROOT>,