target/riscv: Add *envcfg.PBMTE related check in address translation

target/riscv: Add *envcfg.PBMTE related check in address translation

menvcfg.PBMTE bit controls whether the Svpbmt extension is available
for use in S-mode and G-stage address translation.

henvcfg.PBMTE bit controls whether the Svpbmt extension is available
for use in VS-stage address translation.

Set *envcfg.PBMTE default true for backward compatibility.

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20230224040852.37109-5-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>