[PATCH 1/2] Misc. typos

From 68d431b4c14ad60a778ee93c1f59ecc4b931950e Mon Sep 17 00:00:00 2001
Found via `codespell -q 3 -I ../eigen-word-whitelist.txt` where the whitelists consists of:
```
als
ans
cas
dum
lastr
lowd
nd
overfl
pres
preverse
substraction
te
uint
whch
```
---
 CMakeLists.txt                                | 26 +++++++++----------
 Eigen/src/Core/GenericPacketMath.h            |  2 +-
 Eigen/src/SparseLU/SparseLU.h                 |  2 +-
 bench/bench_norm.cpp                          |  2 +-
 doc/HiPerformance.dox                         |  2 +-
 doc/QuickStartGuide.dox                       |  2 +-
 .../Eigen/CXX11/src/Tensor/TensorChipping.h   |  6 ++---
 .../Eigen/CXX11/src/Tensor/TensorDeviceGpu.h  |  2 +-
 .../src/Tensor/TensorForwardDeclarations.h    |  4 +--
 .../src/Tensor/TensorGpuHipCudaDefines.h      |  2 +-
 .../Eigen/CXX11/src/Tensor/TensorReduction.h  |  2 +-
 .../CXX11/src/Tensor/TensorReductionGpu.h     |  2 +-
 .../test/cxx11_tensor_concatenation.cpp       |  2 +-
 unsupported/test/cxx11_tensor_executor.cpp    |  2 +-
 14 files changed, 29 insertions(+), 29 deletions(-)

doc/HiPerformance.dox

@@ -105,7 +105,7 @@ m1.noalias() += m2 * m3; \endcode</td>
 <td>First of all, here the .noalias() in the first expression is useless because
     m2*m3 will be evaluated anyway. However, note how this expression can be rewritten
     so that no temporary is required. (tip: for very small fixed size matrix
-    it is slighlty better to rewrite it like this: m1.noalias() = m2 * m3; m1 += m4;</td>
+    it is slightly better to rewrite it like this: m1.noalias() = m2 * m3; m1 += m4;</td>
 </tr>
 <tr class="alt">
 <td>\code