pmdomain: samsung: plug potential memleak during probe

pmdomain: samsung: plug potential memleak during probe

of_genpd_add_provider_simple() could fail, in which case this code
leaks the domain name, pd->pd.name.

Use devm_kstrdup_const() to plug this leak. As a side-effect, we can
simplify existing error handling.

Fixes: c09a3e6c97f0 ("soc: samsung: pm_domains: Convert to regular platform driver")
Cc: stable@vger.kernel.org
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>