Optimize the RVV implementation of ZROT when inc_x and inc_y are
non-unit strides (inc_x != 1, inc_y != 1).
Reorder several operations to reduce vector register pressure and
avoid unnecessary vector register spill to the stack. This helps GCC
keep vector values in registers and reduces redundant spill/reload
instructions, improving runtime performance.
No functional change.
Signed-off-by: daichengrong <daichengrong@iscas.ac.cn>