[wpiutil] Upgrade to LLVM 16.0.6 (#5435)

Fixes #5332.

upstream_utils/llvm_patches/0015-Delete-numbers-from-MathExtras.patch

@@ -8,11 +8,11 @@ Subject: [PATCH 15/30] Delete numbers from MathExtras
  1 file changed, 36 deletions(-)
 
 diff --git a/llvm/include/llvm/Support/MathExtras.h b/llvm/include/llvm/Support/MathExtras.h
-index fac12dd0e4c6316ff4887542dd59adc954f099e4..e8f1f2aca6106af3885468f686331d8b083630d7 100644
+index 062ed2f4057820547cc6bfc4c91e7a13ceaa2f8a..cc0c1cbd1c8bb523bce720b9783afad7f602c88c 100644
 --- a/llvm/include/llvm/Support/MathExtras.h
 +++ b/llvm/include/llvm/Support/MathExtras.h
-@@ -50,42 +50,6 @@ enum ZeroBehavior {
-   ZB_Width
+@@ -32,42 +32,6 @@ enum ZeroBehavior {
+   ZB_Max
  };
  
 -/// Mathematical constants.
@@ -51,6 +51,6 @@ index fac12dd0e4c6316ff4887542dd59adc954f099e4..e8f1f2aca6106af3885468f686331d8b
 -                phif        = 1.61803399F; // (0x1.9e377aP+0) https://oeis.org/A001622
 -} // namespace numbers
 -
- namespace detail {
- template <typename T, std::size_t SizeOfT> struct TrailingZerosCounter {
-   static unsigned count(T Val, ZeroBehavior) {
+ /// Count number of 0's from the least significant bit to the most
+ ///   stopping at the first 1.
+ ///