memory: samsung: exynos5422-dmc: handle clk_set_parent() failure

[ Upstream commit 132c17c3 ]

clk_set_parent() can fail and ignoring such case could lead to invalid
clock setup for given frequency.

Addresses-Coverity: Unchecked return value
Fixes: 6e7674c3 ("memory: Add DMC driver for Exynos5422")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://lore.kernel.org/r/20210407154535.70756-1-krzysztof.kozlowski@canonical.com


Signed-off-by: Sasha Levin <sashal@kernel.org>