mmc: sdhci: Read capabilities register1 and update host caps

This patch reads the capabilities register1 and update the host
caps accordingly for mmc layer usage. This patch mainly reads
for UHS capabilities inorder to support SD3.0.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>