[PATCH v3 0/2]MMC:implement eMMC4.4 standard HW reset feature

[Chuanxiao Dong <chuanxiao.dong@intel.com>]

Hello Chris,
	  These are the version 3 of HW reset feature implementation. Since I
	  didnot get any response from the version 2 and version1 patches, I am
	  not sure whether I need to change. So just did a little change in
	  form.

	  The 2 patches implemented eMMC4.4 hardware reset feature in core layer
	  and sdhci host layer, but need each sdhci host controller to implement
	  the real reset part specially.

	  patch 0001: implemented eMMC4.4 hardware reset feature in mmc core
	  layer. Added reinit callback in mmc_bus_ops and hardware_reset
	  callback in mmc_host_ops.
	  patch 0002: implemented hardware reset callback in sdhci host layer.
	  Added reset_emmc callback in sdhci_ops.

	  changelog:
	  patch 0001: add a error check when switch to enable HW reset bit
	  failed. Also add some comment to explain the added 2 new callbacks.
	  patch 0002: add some comment to explain the reset_emmc callback.

Thanks
Chuanxiao