Misc. bug: RISCV output bug when using rvv with vlen > 256bit

[grigohas]

Name and Version

./llama-cli latest version ubuntu linux riscv

Operating systems

Linux

Which llama.cpp modules do you know to be affected?

llama-cli

Problem description & steps to reproduce

The generated output of llama-cli in riscv env with rvv enabled consists of trash when vlen is greater than 256bits

First Bad Commit

No response

Relevant log output

No response