target/riscv: support cache-related PMU events in virtual mode

target/riscv: support cache-related PMU events in virtual mode

let tlb_fill() function also increments PMU counter when it is from
two-stage translation, so QEMU could also monitor these PMU events when
CPU runs in VS/VU mode (like running guest OS).

Signed-off-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221123090635.6574-1-jim.shu@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>