phy: amlogic: phy-meson-axg-mipi-pcie-analog: Hold reference returned by of_get_parent()

phy: amlogic: phy-meson-axg-mipi-pcie-analog: Hold reference returned by of_get_parent()

As the of_get_parent() will increase the refcount of the node->parent
and the reference will be discarded, so we should hold the reference
with which we can decrease the refcount when done.

Fixes: 8eff8b4e22d9 ("phy: amlogic: phy-meson-axg-mipi-pcie-analog: add support for MIPI DSI analog")
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220915093506.4009456-1-windhl@126.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>