hw/riscv: iommu-trap: remove .impl.unaligned = true

The riscv_iommu_trap_ops MemoryRegionOps specifies that unaligned accesses are not valid for this device but that it does implement them. This doesn't make much sense, and we want to add an assertion that registered MRs don't specify this invalid combination of settings. Drop .impl.unaligned = true, with no behaviour change. Signed-off-by: CJ Chen <cjchen@igel.co.jp> Acked-by: Tomoyuki Hirose <hrstmyk811m@gmail.com> Reported-by: Tomoyuki Hirose <hrstmyk811m@gmail.com> Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> [PMM: reworded commit message] Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Link: https://lore.kernel.org/r/20260428093339.2087081-2-peter.maydell@linaro.org Signed-off-by: Peter Xu <peterx@redhat.com>