fix(32-wallclock-profiler): use absolute path to find tool paths

[jiangyinzuo]

Problem:

Path(__file__) can be ".", in such case self.oncpu_tool is "oncputime", which can not be found by the shell.

Solution:

Translate Path(__file__) to absolute path.

Please try to use the copilot to summary your PR. You don't need to fill all info below, just it can help giving your a checklist.

Description

Fixes # (issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• Test A
• Test B

Test Configuration:

• Firmware version:
• Hardware:
• Toolchain:
• SDK:

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[yunwei37]

Thanks!