arm64/sme: Provide ABI documentation for SME

mainline inclusion
from mainline-v5.19-rc1
commit 96d32e63
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8E73O
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=96d32e630935c1636b0236c88779e81eff120e0a



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Provide ABI documentation for SME similar to that for SVE. Due to the very
large overlap around streaming SVE mode in both implementation and
interfaces documentation for streaming mode SVE is added to the SVE
document rather than the SME one.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-5-broonie@kernel.org


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>