Fix ptrsize for ARM to not return 2 ever

[lain3d]

Description/Motivation/Screenshots

This changes the ptrsize on ARM to properly reflect that ptrsize will always be 4 even in thumb mode. This allows the stack and tele to both increment by 4 instead of 2, properly allowing gef to dereference pointers.

Relevant code:

    @property
    def instruction_length(self) -> Optional[int]:
        # Thumb instructions have variable-length (2 or 4-byte)
        return None if self.is_thumb() else 4

    @property
    def ptrsize(self) -> int:
        return 4

Against which architecture was this tested ?

"Tested" indicates that the PR works and the unit test (i.e. make test) run passes without issue.

• x86-32
• x86-64
• ARM
• AARCH64
• MIPS
• POWERPC
• SPARC
• RISC-V

Checklist

• My PR was done against the dev branch, not main.
• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• If my change adds new code, adequate tests have been added.
• I have read and agree to the CONTRIBUTING document.