target/riscv: add ssu64xl

ssu64xl is defined in RVA22 as:

"sstatus.UXL must be capable of holding the value 2 (i.e., UXLEN=64 must
be supported)."

This is always true in TCG and it's mandatory for RVA23, so claim
support for it.

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: <20250115184316.2344583-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.c

@@ -213,6 +213,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(sstc, PRIV_VERSION_1_12_0, ext_sstc),
     ISA_EXT_DATA_ENTRY(sstvala, PRIV_VERSION_1_12_0, has_priv_1_12),
     ISA_EXT_DATA_ENTRY(sstvecd, PRIV_VERSION_1_12_0, has_priv_1_12),
+    ISA_EXT_DATA_ENTRY(ssu64xl, PRIV_VERSION_1_12_0, has_priv_1_12),
     ISA_EXT_DATA_ENTRY(supm, PRIV_VERSION_1_13_0, ext_supm),
     ISA_EXT_DATA_ENTRY(svade, PRIV_VERSION_1_11_0, ext_svade),
     ISA_EXT_DATA_ENTRY(svadu, PRIV_VERSION_1_12_0, ext_svadu),