PCI: exynos: Turn off power of phy block when link failed

When link failed, there is no need to turn on phy block. Also,
turning on phy block is added, in order to turn on phy block
regardless of the default value of phy registers.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>