Update Eigen to commit:38b9cc263bbaeb03ce408a4e26084543a6c0dedb

CHANGELOG
=========
38b9cc263 - Fix warnings about repeated deinitions of macros.
f02f89bf2 - Don't redefine EIGEN_DEFAULT_IO_FORMAT in main.h.
9148c47d6 - Vectorize isfinite and isinf.
5a9f66fb3 - Fix Thread tests
c4d84dfdd - Fix compilation failures on constexpr matrices with GCC 14
99adca8b3 - Incorporate Threadpool in Eigen Core
d165c7377 - Format EIGEN_STATIC_ASSERT() as a statement macro
f78dfe36b - use built in alloca with align if available
b9b1c8661 - Suppress C++23 deprecation warnings for std::has_denorm and std::has_denorm_loss
3d2e738f2 - fix performance-no-int-to-ptr
de8013fa6 - Fix ubsan failure in array_for_matrix
5e4f3475b - Remove call to deprecated method initParallel() in SparseDenseProduct.h
59cf0df1d - SparseMatrix::insert add checks for valid indices
c0fe6ce22 - Fixed a clerical error at documentation of class Matrix.
afb17288c - Fix gcc6 compile error.
4d1d14e06 - Change predux on PowerPC for Packet4i to NOT saturate the sum of the elements (like other architectures).
ff174f792 - fix issue: cmake package does not set include path correctly

PiperOrigin-RevId: 638732445
Change-Id: I550ab37d222c05c774ae2959fe6b7a6bbb61e01a
37 files changed