Update Eigen to commit:6156797016164b87b3e360e02d0e4107f7f66fbc

CHANGELOG
=========
615679701 - Revert "Add template to specify QR permutation index type, Fix ColPivHouseholderQR Lapacke bindings"
be7791e09 - Add template to specify QR permutation index type, Fix ColPivHouseholderQR Lapacke bindings
9463fc95f - change insert strategy
c54785b07 - Fix error: unused parameter '\''tmp'\'' [-Werror,-Wunused-parameter] on clang/32-bit arm
f47472603 - Add missing header for GPU tests.
81172cbdc - Overhaul Sparse Core
925518189 - Modified spbenchsolver help message because it could be misunderstood
d20fe21ae - Improve performance for Power10 MMA bfloat16 GEMM
fe7f52778 - Fix guard macros for emulated FP16 operators on GPU
b8422c99c - Update file jacobisvd.cpp
262194f12 - Fix a bunch of minor build and test issues.

PiperOrigin-RevId: 501682808

Author: tensorflower-gardener

third_party/eigen3/workspace.bzl

@@ -7,8 +7,8 @@ def repo():
 
     # Attention: tools parse and update these lines.
     # LINT.IfChange
-    EIGEN_COMMIT = "3564668908afc66351c1c3cc47dca2fcdb91dc12"
-    EIGEN_SHA256 = "242bf03ec7371f48c3c5b61aacf313659be1d323b94e21e0002ee927ebb3add7"
+    EIGEN_COMMIT = "6156797016164b87b3e360e02d0e4107f7f66fbc"
+    EIGEN_SHA256 = "dc9d26d5bcc6848eb188c672355b309170b2ff7acd483cab08f47b7d5f3f496e"
     # LINT.ThenChange(//tensorflow/lite/tools/cmake/modules/eigen.cmake)
 
     tf_http_archive(