mmc: host: Add variant ops for cqhci crypto

QTI implementation for block keyslot manager and
crypto vops for crypto support in CQHCI.

Fixed compilation issues in cqhci-crypto-qti.c and merge
conflicts in sdhci-msm.c and Kconfig files.
(cherry picked from mainline kernel_msm-4.19 commit  5220e65f).

Conflicts:
       drivers/mmc/host/Kconfig
       drivers/mmc/host/sdhci-msm.c

Test:
1. Device booted upto UI with File Based Encryption enabled.
2. Key insertion using fscryptctl tool.
3. Created new files under /data and checked retention across
   multiple re-boots.
4. vts_kernel_encryption_test tests.
5. check_encryption test for verifying metadata encryption.

Change-Id: I9b64f85ca97c269a6ecd6fde2bb693745d4c43d4
Signed-off-by: Neeraj Soni <neersoni@codeaurora.org>
Signed-off-by: Vaibhav Agrawal <vagrawa@codeaurora.org>