[llvm] [AVR] Remove extra ROL / ROR operands (PR #117510)

[Ben Shi via llvm-commits]

https://github.com/benshi001 approved this pull request.

LGTM. It would be better to rename the title of commit message to `[AVR][NFC] Remove unnecessary operands of ROL/ROR`

https://github.com/llvm/llvm-project/pull/117510