[RISCV] Move shuffle-reverse test to rvv directory. NFC

Test is related to vectors so probably belongs in the rvv directory

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D147412

diff --git a/llvm/test/CodeGen/RISCV/shuffle-reverse.ll b/llvm/test/CodeGen/RISCV/rvv/shuffle-reverse.ll
similarity index 100%
rename from llvm/test/CodeGen/RISCV/shuffle-reverse.ll
rename to llvm/test/CodeGen/RISCV/rvv/shuffle-reverse.ll