target/arm: Drop EL3 no EL2 fallbacks

target/arm: Drop EL3 no EL2 fallbacks

Drop el3_no_el2_cp_reginfo, el3_no_el2_v8_cp_reginfo, and the local
vpidr_regs definition, and rely on the squashing to ARM_CP_CONST
while registering for v8.

This is a behavior change for v7 cpus with Security Extensions and
without Virtualization Extensions, in that the virtualization cpregs
are now correctly not present.  This would be a migration compatibility
break, except that we have an existing bug in which migration of 32-bit
cpus with Security Extensions enabled does not work.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220506180242.216785-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>