dt-bindings: display: msm/dsi: Fix the PHY regulator supply props

dt-bindings: display: msm/dsi: Fix the PHY regulator supply props

BugLink: http://bugs.launchpad.net/bugs/1786352
[ Upstream commit 8c4905fd4939c59e0f7993ba34883e328eef4b59 ]

The PHY regulator supply names vary across different PHY versions.
Mention explicitly which PHYs require which supplies.

Cc: Rob Herring <robh@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>