phy: qcom: qmp-combo: Rename 'mode' to 'phy_mode'

phy: qcom: qmp-combo: Rename 'mode' to 'phy_mode'

There are a numbers of ""modes"" involved: USB mode, Type-C mode (with
its altmodes), phy_mode and QMP_PHY mode (DP/combo/USB/off).

Rename the generic sounding 'mode' to 'phy_mode' to hopefully make
the code easier to follow.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on Lenovo Thinkpad T14S
Link: https://lore.kernel.org/r/20250807-topic-4ln_dp_respin-v4-2-43272d6eca92@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>