[zircon][sdio]Add UHS support

This changeset adds support for ultra high speed for sdio.
Astro fails the read commands when frequency is more than 25Mhz,
mostly related to the PORT issues on it, which needs further investigation.

Test: Tested SDIO probing on Vim2 and Astro.

Change-Id: Ibb6cb4f79203ea76b300c3f0ea6fe06f772bcad5

[zircon][sdio] Add more protocol ops

This changeset adds proto ops for getting hw info and current blk size of sdio
device. I had to do some refactoring to make the data structures more
secure to use in the upper layers.

Test: sdio test on vim2 using the apis

Change-Id: If439f263b1a3cd8c90a975782b33f57c20d80af2

[zircon][sdio] Add SDIO protocol

SDIO protocol provides read/write and other control functions for upper layers.
I will be using the protocol and publishing the sdio device in a future changeset.
This changeset also does not use DMA for data transfers. I will be adding that
in a separate changeset.

Test: SDIO probe on Estelle and VIM.

Change-Id: I1c895e642a4cf20b1be227a46256f8d34d1d578e

[zircon][sdio]Add support for core sdio

This changeset probes and initializes the sdio functions. It also
implements the rw commands(CMD52 and CMD53) for control/IO operations
on SDIO

Change-Id: I8585c064602cae6256acc3074371d887aa014252