target/riscv: moving some insns close to similar insns

target/riscv: moving some insns close to similar insns

lwu and ld are functionally close to the other loads, but were after the
stores in the source file.
Similarly, xor was away from or and and by two arithmetic functions, while
the immediate versions were nicely put together.
This patch moves the aforementioned loads after lhu, and xor above or,
where they more logically belong.

Signed-off-by: Frédéric Pétrot <frederic.petrot@univ-grenoble-alpes.fr>
Co-authored-by: Fabien Portas <fabien.portas@grenoble-inp.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20220106210108.138226-9-frederic.petrot@univ-grenoble-alpes.fr
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>