Add support for the Inline Crypto Engine (ICE) key programming interface
that's needed for the ufs-qcom driver to use inline encryption on
Snapdragon SoCs.  This interface consists of two SCM calls: one to program
a key into a keyslot, and one to invalidate a keyslot.

Although the UFS specification defines a standard way to do this, on these
SoCs the Linux kernel isn't permitted to access the needed crypto
configuration registers directly; these SCM calls must be used instead.

Link: https://lore.kernel.org/r/20200710072013.177481-2-ebiggers@kernel.orgAcked-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>