primecount-7.14-bp160.1.12

- Update to primecount-7.14 (API & ABI are backwards compatible).
- Fix libdivide.h issue with GCC 15: #76.
- Move x86 cpuid code from cpuid.hpp to src/x86/cpuid.cpp.
- Move generate.hpp code to src/generate_primes.cpp.
- Move generate_phi.hpp code to src/phi_vector.cpp.
- int128_t.hpp: Rename namespace port to pstd (portable std namespace).
- Sieve.hpp: Tune AVX512 code.
- Sieve.hpp: Branchfree bitmask calculation.
- cpu_supports_popcnt.hpp: Simplify, move preprocessor checks to new multiarch_x86_popcnt.cmake.
- multiarch_avx512_vpopcnt.cmake: Tune AVX512 code.
- multiarch_x86_popcnt.cmake: Detect x86 POPCNT.
- CMakeLists.txt: Use CMake list for all compile time definitions.

- Update to primecount-7.13 (API & ABI are backwards compatible).
- CMakeLists.txt: New WITH_MULTIARCH option (default ON).
- Sieve.hpp: New AVX512 popcount algorithm for x86 CPUs.
- Sieve.hpp: New ARM SVE popcount algorithm.
- int128.cmake: Improve int128_t support for Windows.
- OpenMP.cmake: Improve LLVM/Clang OpenMP detection.
- Add preliminary MSVC 128-bit support.

- Update to primecount-7.12 (API & ABI are backwards compatible).
- On x86 CPUs check using CPUID if CPU supports POPCNT.
- CMakeLists.txt: Remove WITH_POPCNT=OFF option.
- New dynamic/adaptive load balancing for AC algorithm.
- LogarithmicIntegral.cpp: Fix infinite loop on Linux i386.
- RiemannR.cpp: Fix infinite loop on Linux i386.
- RiemannR.cpp: Faster and simpler RiemannR_inverse(x).

- Update to primecount-7.11 (API & ABI are backwards compatible).
- Increase pi(x) cache size to 2 KiB.
- Detect incompatible command-line options.
- Faster RiemannR(x) and RiemannR_inverse(x) implementations.
- test/iroot.cpp: Fix musl libc issue.
- test/Li.cpp: Speed up test.
- Renamed option --Ri to -R or --RiemannR.
- Renamed option --Ri-inverse to --RiemannR-inverse.
- Improve status output on Windows.

- Update to primecount-7.10 (API & ABI are backwards compatible).
- Improve CMake libatomic detection.
- Fix potential integer overflows in Li_inverse(x) and Ri_inverse(x).
- Added new internal nth_prime_approx(n).