Roll libunwind from 21acd3f62203 to bbd954d05f4b (1 revision)

https://chromium.googlesource.com/external/github.com/llvm/llvm-project/libunwind.git/+log/21acd3f62203..bbd954d05f4b

2021-10-26 ldionne.2@gmail.com [libunwind] Take 2: Use the from-scratch testing configuration by default

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/libunwind-chromium
Please CC hans@chromium.org,thakis@chromium.org on the revert to ensure that a human
is aware of the problem.

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To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

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https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

Tbr: hans@chromium.org,thakis@chromium.org
Change-Id: I2cb74d489f4b118c258e27c9fb9f52ee08ab0b6f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3243996
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Bot-Commit: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#934966}

DEPS

@@ -397,7 +397,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'libunwind_revision':    '21acd3f62203c561edc54fedf549eb38da6081c5',
+  'libunwind_revision':    'bbd954d05f4b01d4ed2e1f912bb5a0ff555e1a39',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.