media: exynos4-is: Fix PM disable depth imbalance in fimc_is_probe

If probe fails then we need to call pm_runtime_disable() to balance
out the previous pm_runtime_enable() call.

Fixes: 9a761e43 ("[media] exynos4-is: Add Exynos4x12 FIMC-IS driver")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>