The current parsing logic for the target string assumes it follows the
format `<kind>-<triple>-<target id>:<feature>`, such as
`hipv4-amdgcn-amd-amdhsa-gfx1030:+xnack`.
Specifically, it assumes that `<target id>` does not contain any `-`,
relying on `rsplit` for parsing.
However, this assumption breaks for AMDGPU's generic targets, which may
contain one or more `-`, such as `gfx10-3-generic` or `gfx12-generic`.
As a result, the existing approach using `rstrip` is no longer reliable.
This patch reworks the parsing logic to handle target strings more
robustly, including support for generic targets.
The bundler now strictly requires a 4-field target triple.
Additionally, a new Python helper function has been added to `config.py`
to normalize the target triple into the 4-field format when it is not,
ensuring tests pass reliably.