target/riscv: do not use translator_ldl in opcode_at

opcode_at is used only in semihosting checks to match opcodes with expected
pattern.

This is not a translator and if we got following assert if page is not in TLB:
qemu-system-riscv64: ../accel/tcg/translator.c:363: record_save: Assertion
`offset == db->record_start + db->record_len' failed.

Fixes: 1f9c4462334f ("target/riscv: Use translator_ld* for everything")
Signed-off-by: Vladimir Isaev <vladimir.isaev@syntacore.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250815140633.86920-1-vladimir.isaev@syntacore.com>
[ Changes by AF:
 - Fixup header includes after rebase
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>