iio: temperature: mlx90635: Fix ERR_PTR dereference in mlx90635_probe()

In the Linux kernel, the following vulnerability has been resolved: iio: temperature: mlx90635: Fix ERR_PTR dereference in mlx90635_probe() When devm_regmap_init_i2c() fails, regmap_ee could be error pointer, instead of checking for IS_ERR(regmap_ee), regmap is checked which looks like a copy paste error.