hw/arm/virt: Consolidate valid CPU types

hw/arm/virt: Consolidate valid CPU types

It's found that some of the CPU type names in the array of valid
CPU types are invalid because their corresponding classes aren't
registered, as reported by Peter Maydell.

[gshan@gshan build]$ ./qemu-system-arm -machine virt -cpu cortex-a9
qemu-system-arm: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, (null), (null), (null),
(null), (null), (null), (null), (null), (null), (null), (null), max

Fix it by consolidating the array of valid CPU types. After it's
applied, we have the following output when TCG is enabled.

[gshan@gshan build]$ ./qemu-system-arm -machine virt -cpu cortex-a9
qemu-system-arm: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, max

[gshan@gshan build]$ ./qemu-system-aarch64 -machine virt -cpu cortex-a9
qemu-system-aarch64: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, cortex-a35, cortex-a55,
cortex-a72, cortex-a76, cortex-a710, a64fx, neoverse-n1, neoverse-v1,
neoverse-n2, cortex-a53, cortex-a57, max

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2084
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-id: 20240111051054.83304-1-gshan@redhat.com
Fixes: fa8c617791 ("hw/arm/virt: Check CPU type in machine_run_board_init()")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>