target/riscv: deprecate capital 'Z' CPU properties

target/riscv: deprecate capital 'Z' CPU properties

At this moment there are eleven CPU extension properties that starts
with capital 'Z': Zifencei, Zicsr, Zihintntl, Zihintpause, Zawrs, Zfa,
Zfh, Zfhmin, Zve32f, Zve64f and Zve64d. All other extensions are named
with lower-case letters.

We want all properties to be named with lower-case letters since it's
consistent with the riscv-isa string that we create in the FDT. Having
these 11 properties to be exceptions can be confusing.

Deprecate all of them. Create their lower-case counterpart to be used as
maintained CPU properties. When trying to use any deprecated property a
warning message will be displayed, recommending users to switch to the
lower-case variant:

./build/qemu-system-riscv64 -M virt -cpu rv64,Zifencei=true --nographic
qemu-system-riscv64: warning: CPU property 'Zifencei' is deprecated. Please use 'zifencei' instead

This will give users some time to change their scripts before we remove
the capital 'Z' properties entirely.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231009112817.8896-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>