i2c: gxp: fix an error code in probe

This is passing IS_ERR() instead of PTR_ERR() so instead of an error
code it prints and returns the number 1.

Fixes: 4a55ed6f ("i2c: Add GXP SoC I2C Controller")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Nick Hawkins <nick.hawkins@hpe.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

drivers/i2c/busses/i2c-gxp.c

@@ -516,7 +516,7 @@ static int gxp_i2c_probe(struct platform_device *pdev)
 		i2cg_map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 							   "hpe,sysreg");
 		if (IS_ERR(i2cg_map)) {
-			return dev_err_probe(&pdev->dev, IS_ERR(i2cg_map),
+			return dev_err_probe(&pdev->dev, PTR_ERR(i2cg_map),
 					     "failed to map i2cg_handle\n");
 		}