arm64/sysreg: Remove stray SMIDR_EL1 defines

SMIDR_EL1 was converted to automatic generation but some of the constants
for fields in it were mistakenly left, remove them.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-2-broonie@kernel.org


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>