[llvm] [MC][RISCV] Add assembly syntax highlighting for RISCV (PR #65853)

[Yingwei Zheng via llvm-commits]

================
@@ -256,6 +278,8 @@ void RISCVInstPrinter::printSpimm(const MCInst *MI, unsigned OpNo,
   if (Opcode == RISCV::CM_PUSH)
     Spimm = -Spimm;
 
+  // RAII guard for ANSI color escape sequences
----------------
dtcxzyw wrote:

`markup` simply returns a temporary wrapper `WithMarkup`. It set/reset the foreground color of the terminal in its ctor/dtor.

https://github.com/llvm/llvm-project/pull/65853