This PR continues https://github.com/llvm/llvm-project/pull/101732
changes in virtual register processing aimed to improve correctness of
emitted MIR between passes from the perspective of MachineVerifier.
Namely, the following changes are introduced:
* register classes (lib/Target/SPIRV/SPIRVRegisterInfo.td) and
instruction patterns (lib/Target/SPIRV/SPIRVInstrInfo.td) are corrected
and simplified (by removing unnecessary sophisticated options) -- e.g.,
this PR gets rid of duplicating 32/64 bits patterns, removes ANYID
register class and simplifies definition of the rest of register
classes,
* hardcoded LLT scalar types in passes before instruction selection are
corrected -- the goal is to have correct bit width before instruction
selection, and use 64 bits registers for pattern matching in the
instruction selection pass; 32-bit registers remain where they are
described in such terms by SPIR-V specification (like, for example,
creation of virtual registers for scope/mem semantics operands),
* rework virtual register type/class assignment for calls/builtins
lowering,
* a series of minor changes to fix validity of emitted code between
passes:
  - ensure that that bitcast changes the type,
  - fix the pattern for instruction selection for OpExtInst,
  - simplify inline asm operands usage,
  - account for arbitrary integer sizes / update legalizer rules;
* add '-verify-machineinstrs' to existed test cases.

See also https://github.com/llvm/llvm-project/issues/88129 that this PR
may resolve.

This PR fixes a great number of issues reported by MachineVerifier and,
as a result, reduces a number of failed test cases for the mode with
expensive checks set on from ~200 to ~57.

This pull request aims to remove any dependency on OpenCL/SPIR-V type
information in LLVM IR metadata. While, using metadata might simplify
and prettify the resulting SPIR-V output (and restore some of the
information missed in the transformation to opaque pointers), the
overall methodology for resolving kernel parameter types is highly
inefficient.

The high-level strategy is to assign kernel parameter types in this order:

1. Resolving the types using builtin function calls as mangled names
must contain type information or by looking up builtin definition in
SPIRVBuiltins.td. Then:

- Assigning the type temporarily using an intrinsic and later setting
the right SPIR-V type in SPIRVGlobalRegistry after IRTranslation
 - Inserting a bitcast
2. Defaulting to LLVM IR types (in case of pointers the generic i8*
type or types from byval/byref attributes)

In case of type incompatibility (e.g. parameter defined initially as
sampler_t and later used as image_t) the error will be found early on
before IRTranslation (in the SPIRVEmitIntrinsics pass).

This pull request fixes an issue with missing vector element count
immediate in OpExtInst calls and adds a case for generating bitcasts
before GEPs for kernel arguments of non-matching pointer type. The new
LITs are based on basic/vload_local and basic/vload_global OpenCL CTS
tests. The tests after this change pass SPIR-V validation.