Support lists of variables to be declared

[zluda-violet]

For example,

.reg .u32 a, b;

[Copilot]

Pull Request Overview

This PR adds support for parsing lists of variables in PTX declarations, enabling syntax like .reg .u32 a, b; where multiple variables of the same type and state space can be declared in a single statement.

Key changes:

• Refactored Variable struct to separate type/space information from name into VariableInfo
• Modified MultiVariable from struct to enum to handle both parameterized variables and comma-separated name lists
• Updated parser to handle comma-separated variable names in declarations

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
ptx_parser/src/ast.rs	Restructured Variable and MultiVariable types to support multiple names
ptx_parser/src/lib.rs	Updated parser logic to handle comma-separated variable names and restructured data
ptx/src/test/spirv_run/reg_multi.ptx	Added test case demonstrating multi-variable declaration syntax
ptx/src/test/spirv_run/mod.rs	Added test case for reg_multi functionality
ptx/src/test/ll/reg_multi.ll	Expected LLVM output for reg_multi test
ptx/src/pass/*.rs	Updated all passes to use new Variable/VariableInfo structure

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[vosen]

Looks good, minor nit