Add support for Flash Memory Protector (FMP), which is the inline
encryption hardware on Exynos and Exynos-based SoCs.

Specifically, add support for the "traditional FMP mode" that works on many
Exynos-based SoCs including gs101.  This is the mode that uses "software
keys" and is compatible with the upstream kernel's existing inline
encryption framework in the block and filesystem layers.  I plan to add
support for the wrapped key support on gs101 at a later time.

Tested on gs101 (specifically Pixel 6) by running the 'encrypt' group of
xfstests on a filesystem mounted with the 'inlinecrypt' mount option.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20240708235330.103590-7-ebiggers@kernel.orgReviewed-by: Peter Griffin <peter.griffin@linaro.org>
Tested-by: Peter Griffin <peter.griffin@linaro.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>