Split HummingBoard DT to support s/dl and d/q

References from Russell King work on CuBox-i

Signed-off-by: Rabeeh Khoury <rabeeh@solid-run.com>
Micro SD UHS-1 support

1. Observations showed that there are UHS-1 micro SD cards that doesn't report
   that they support UHS-1 after warm boot (WDOG).
   This patch adds gpio voltage regulator control to the micro SD supply
   voltage therefore the micro SD card is being power cycled on every boot thus
   preventing the issue of not reporting UHS-1.
2. Add support for 3.3v and 1.8v voltage switchover (HummingBoard rev 3.0).

Signed-off-by: Rabeeh Khoury <rabeeh@solid-run.com>
Minor fix for USB enable pad settings

Bit 30 doesn't exists. So don't use it.

Signed-off-by: Rabeeh Khoury <rabeeh@solid-run.com>