phy: qcom: qmp-pcie: restore compatibility with existing DTs

[ Upstream commit 912cee11c14376a6f707d72fcaf343a40bff48e8 ]

Existing device trees specify only a single clock-output-name for the
PCIe PHYs. The function phy_aux_clk_register() expects a second entry in
that property. When it doesn't find it, it returns an error, thus
failing the probe of the PHY and thus breaking support for the
corresponding PCIe host.

Follow the approach of the combo USB+DT PHY and generate the name for
the AUX clocks instead of requiring it in DT.

Fixes: 583ca9cc

 ("phy: qcom: qmp-pcie: register second optional PHY AUX clock")
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240614-fix-pcie-phy-compat-v3-1-730d1811acf4@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>