[AArch64] Refactor @plt, @gotpcrel, and @AUTH to use parseDataExpr

Following PR #132569 (RISC-V), which added `parseDataExpr` for parsing
expressions in data directives (e.g., `.word`), this PR migrates AArch64
`@plt`, `@gotpcrel`, and `@AUTH` from the `parsePrimaryExpr` workaround
to `parseDataExpr`. The goal is to align with the GNU assembler model,
where relocation specifiers apply to the entire operand rather than
individual terms, reducing complexity-especially evident in `@AUTH`
parsing.

Note: AArch64 ELF lacks an official syntax for data directives
(#132570). A prefix notation might be a preferable future direction.
I recommend `%specifier(expr)`.

AsmParser's `@specifier` parsing is suboptimal, necessitating lexer
workarounds. `@` might appear multiple times in an operand.
We should not use `@` beyond the existing AArch64 Mach-O instruction
operands.

In the test elf-reloc-ptrauth.s, many errors are now reported at parse
time.

Pull Request: https://github.com/llvm/llvm-project/pull/134202

0 files changed, 0 insertions, 0 deletions