target/riscv: add RVA22S64 profile

target/riscv: add RVA22S64 profile

The RVA22S64 profile consists of the following:

- all mandatory extensions of RVA22U64;
- priv spec v1.12.0;
- satp mode sv39;
- Ssccptr, a cache related named feature that we're assuming always
  enable since we don't implement a cache;
- Other named features already implemented: Sstvecd, Sstvala,
  Sscounterenw;
- the new Svade named feature that was recently added.

Most of the work is already done, so this patch is enough to implement
the profile.

After this patch, the 'rva22s64' user flag alone can be used with the
rva64i CPU to boot Linux:

-cpu rv64i,rva22s64=true

This is the /proc/cpuinfo with this profile enabled:

 # cat /proc/cpuinfo
processor	: 0
hart		: 0
isa		: rv64imafdc_zicbom_zicbop_zicboz_zicntr_zicsr_zifencei_zihintpause_zihpm_zfhmin_zca_zcd_zba_zbb_zbs_zkt_svinval_svpbmt
mmu		: sv39

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-26-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>