devel/abseil: fix __is_trivially_relocatable warnings with clang 21
With clang 21 ports using devel/abseil will run into warnings similar
to:
In file included from /usr/local/include/absl/strings/string_view.h:40:
In file included from /usr/local/include/absl/base/nullability.h:154:
In file included from /usr/local/include/absl/base/internal/nullability_impl.h:23:
/usr/local/include/absl/meta/type_traits.h:527:22: warning: builtin __is_trivially_relocatable is deprecated; use __builtin_is_cpp_trivially_relocatable instead [-Wdeprecated-builtins]
527 | (__is_trivially_relocatable(T) &&
| ^
/usr/local/include/absl/meta/type_traits.h:527:22: warning: builtin __is_trivially_relocatable is deprecated; use __builtin_is_cpp_trivially_relocatable instead [-Wdeprecated-builtins]
/usr/local/include/absl/meta/type_traits.h:147:24: note: in instantiation of template class 'absl::is_trivially_relocatable<absl::str_format_internal::FormatArgImpl>' requested here
147 | : std::conditional<T::value, conjunction<Ts...>, T>::type {};
| ^Upstream abseil fixed this in
https://github.com/abseil/abseil-cpp/commit/a4950fb, so pull it in as
a patch.
PR: 293380
Approved by: danfe (maintainer)
MFH: 2026Q1