block: ioctl support for sanitize in eMMC 4.5

Adding a new ioctl to support sanitize operation in eMMC
cards version 4.5.
The sanitize ioctl support helps performing this operation
via user application.

Change-Id: I79aa4163e7753a75bed5a26a9a92de902b4b9c21
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>