Refactor of the llvm-tblgen source into:
- a "Basic" library, which contains the bare minimum utilities to build
`llvm-min-tablegen`
- a "Common" library which contains all of the helpers for TableGen
backends. Such helpers can be shared by more than one backend, and even
unit tested (e.g. CodeExpander is, maybe we can add more over time)

Fixes #80647

```
find llvm/utils/TableGen -iname "*.h" -o -iname "*.cpp" | xargs clang-format-16 -i
```

Split from #80847

This also includes a few cleanup from Support.

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D121331

Follow-up of D72172 and D72180

This patch passes `uint64_t Address` to print methods of PC-relative
operands so that subsequent target specific patches can change
`*InstPrinter::print{Operand,PCRelImm,...}` to customize the output.

Add MCInstPrinter::PrintBranchImmAsAddress which is set to true by
llvm-objdump.

```
// Current llvm-objdump -d output
aarch64: 20000: bl #0
ppc:     20000: bl .+4
x86:     20000: callq 0

// Ideal output
aarch64: 20000: bl 0x20000
ppc:     20000: bl 0x20004
x86:     20000: callq 0x20005

// GNU objdump -d. The lack of 0x is not ideal because the result cannot be re-assembled
aarch64: 20000: bl 20000
ppc:     20000: bl 0x20004
x86:     20000: callq 20005
```

In `lib/Target/X86/X86GenAsmWriter1.inc` (generated by `llvm-tblgen -gen-asm-writer`):

```
   case 12:
     // CALL64pcrel32, CALLpcrel16, CALLpcrel32, EH_SjLj_Setup, JCXZ, JECXZ, J...
-    printPCRelImm(MI, 0, O);
+    printPCRelImm(MI, Address, 0, O);
     return;
```

Some targets have 2 `printOperand` overloads, one without `Address` and
one with `Address`. They should annotate derived `Operand` properly with
`let OperandType = "OPERAND_PCREL"`.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D76574

Summary:
While working on the GISel Combiner, I noticed I was producing location-less
error messages fairly often and set about fixing this. In the process, I
noticed quite a few places elsewhere in TableGen that also neglected to include
a relevant location.

This patch adds locations to errors that relate to a specific record (or a
field within it) and also have easy access to the relevant location. This is
particularly useful when multiclasses are involved as many of these errors
refer to the full name of a record and it's difficult to guess which substring
is grep-able.

Unfortunately, tablegen currently only supports Record granularity so it's not
currently possible to point at a specific Init so these sometimes point at the
record that caused the error rather than the precise origin of the error.

Reviewers: bogner, aditya_nandakumar, volkan, aemerson, paquette, nhaehnle

Reviewed By: nhaehnle

Subscribers: jdoerfert, nhaehnle, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58077

llvm-svn: 353862

to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

llvm-svn: 258488