mmc: sdhci: Use max timeout and skip timeout calculation

Several data-timeout issues were seen, most of which were
due to the card taking a longer time to respond. This patch
increases the timeout of the controller to 0xF i.e. max
possible.

Change-Id: I54c095cdfff55b444c94e7188df8859727cb9675
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Ram Prakash Gupta <rampraka@codeaurora.org>