phy: qcom-qmp-pcie: support separate tables for EP mode

The PCIe QMP PHY requires different programming sequences when being
used for the RC (Root Complex) or for the EP (End Point) modes. Allow
selecting the submode and thus selecting a set of PHY programming
tables.

Since the RC and EP modes share common some common init sequence, the
common sequence is kept in the main table and the sequence differences
are pushed to the extra tables.

Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>