Fix: Used but undeclared macro 'asm!'.

[Yakkhini]

It‘s an EMERGENCY fix!

I noticed that almost every lab repo autograding failed cause incorrect use of asm! macro in built-in riscv dependency, except:

• They change their os2/Cargo.toml, make the riscv source to Gitee. In this case, line replace function in overwrite.py can't replace riscv to path ../ci-user/riscv
• They just delete the replace function in overwrite.py, like Do not overwrite the riscv to local copy #17
• They didn't set up classroom autograding in GitHub Actions, the deploy action works fine.

The built-in riscv dependency in ci-user must be unusable.

You said make test2 works fine in your environment, please check if your riscv source in Cargo.toml changed to Gitee, or your riscv's macro is correctly writed.

See more deep information, please check this commit.

[nooop3]

Yes, the same error in the local and codespace environments. Related changes:

• Move asm! and global_asm! to core::arch rust-lang/stdarch#1183
• Tracking Issue for asm_const rust-lang/rust#93332

[Yakkhini]

@chyyuu

[chyyuu]

It works! Good JOB! Thanks you!