Register assembly printer passes in the pass registry.

This makes it possible to use `llc -start-before=<target>-asm-printer ...` in tests.

Adds a `char &ID` parameter to the AssemblyPrinter constructor to allow
targets to use the `INITIALIZE_PASS` macros and register the pass in the
pass registry. This currently has a default parameter so it won't break
any targets that have not been updated.

clang -fexperimental-relative-c++-abi-vtables might generate `@plt` and
`@gotpcrel` specifiers in data directives. The syntax is not used in
humand-written assembly code, and is not supported by GNU assembler.
Note: the `@plt` in `.word foo@plt` is different from
the legacy `call func@plt` (where `@plt` is simply ignored).

The `@plt` syntax was selected was simply due to a quirk of AsmParser:
the syntax was supported by all targets until I updated it
to be an opt-in feature in a0671758eb6e52a758bd1b096a9b421eec60204c

RISC-V favors the `%specifier(expr)` syntax following MIPS and Sparc,
and we should follow this convention.

This PR adds support for `.word %pltpcrel(foo+offset)` and
`.word %gotpcrel(foo)`, and drops `@plt` and `@gotpcrel`.

* MCValue::SymA can no longer have a SymbolVariant. Add an assert
  similar to that of AArch64ELFObjectWriter.cpp before
  https://reviews.llvm.org/D81446 (see my analysis at
  https://maskray.me/blog/2025-03-16-relocation-generation-in-assemblers
  if intrigued)
* `jump foo@plt, x31` now has a different diagnostic.

Pull Request: https://github.com/llvm/llvm-project/pull/132569

This moves function as is, improvements to the estimate go into
a subseqent patch.

Converts AMDGPUResourceUsageAnalysis pass from Module to MachineFunction
pass. Moves function resource info propagation to to MC layer (through
helpers in AMDGPUMCResourceInfo) by generating MCExprs for every
function resource which the emitters have been prepped for.

Fixes https://github.com/llvm/llvm-project/issues/64863

This allows lowering individual instructions in a bundle before a single
call to EmitToStreamer for VLIW targets.

Enables MCExpr for HSAMetadata, particularly, HSAMetadata's msgpack format.

Eliminates assumption that MCExpr comments/remarks being emitted are
always resolvable

Redefines the amd_kernel_code_t struct with MCExprs for members that would be
derived from SIProgramInfo MCExpr members.

Convert members in SIProgramInfo affected by variables provided by AMDGPUResourceUsageAnalysis into MCExprs.

Kernel descriptor attributes, with their respective emit and asm parse functionality, converted to MCExpr.

Relands #80855 with fixes