target/nios2 : Explicitly ask for target-endian loads and stores

target/nios2 : Explicitly ask for target-endian loads and stores

When we generate code for guest loads and stores, at the moment they
end up being requests for a host-endian access. So for target-system-nios2
(little endian) a load like
   ldw        r3,0(r4)
results on an x86 host in the TCG IR
   qemu_ld_a32_i32 r3,loc2,al+leul,0
but on s390 it is
   qemu_ld_a32_i32 r3,loc2,al+beul,0

The result is that guests don't work on big-endian hosts.

Use the MO_TE* memops rather than the plain ones.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1693
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230623172556.1951974-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>