Enable fma test on Alpine Linux (musl C library)

[weixlu]

Feature or enhancement

Proposal:

#131313 fix many tests on Alpine Linux (musl C library). About test_fma_zero_result, it says

    # gh-131032: musl is fixed but the fix is not yet released; when the fixed
    # version is known change this to:
    #   or support.linked_to_musl() < (1, <m>, <p>)

And now musl 1.2.6 is available, and I have verified that the test can pass. So let's enable it.

• docker image: alpine:edge
• musl version: 1.2.6-r2
• test result: pass

I also test the older version

• docker image: alpine:3.21
• musl version: 1.2.5-r11
• test result: skipped

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

#131313

Linked PRs

• gh-152563, test_math: Enable fma test on musl 1.2.6 #152564