ARM: tegra: cardhu: add dt entry for fixed regulators

Cadhu have multiple power rails which are controlled by
GPIOs. Add support of these power rail control through
fixed regulators. Add entry for all fixed regulators for
cardhu-a02 and a04.
The details are taken from downstream kernel.

Some points on this change are:

* Add the tps65910-LDO5 entry and make it always ON
 to supply power to SDMMC. Once the sd driver support
 regulator handling, this flag will be remove.

* Dropping registration of rail vdd_sdmmc1 as the gpio
  is used by sdhci power-gpio. This need to fix in
  sdhci driver and then need to add the registration
  mechanism. Just removing power-gpio and adding fixed
  regulator with this gpio is causing the sd  access to
  fail because first probe call of this regulator fails
  due to non-available of parent and so it calls
  gpio_free() which disable the pins in gpio mode make
  pin output to LOW causes power to OFF. In probe retry,
  it got success and it powered-on but it again need to
  do again numeration of card here.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>