boost/1.79.0: Patch Boost.SmartPtr to support a specific variant of PowerPC

[jwillikers]

This patch adds support for CodeWarrior / PowerPC platforms which support the msync instead of the sync assembly instruction.
This change has been fixed upstream in Boost.SmartPtr by boostorg/smart_ptr#95.
THe change should be included in an upcoming upstream release.

Specify library name and version: boost/1.79.0

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• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
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[ghost]

I detected other pull requests that are modifying boost/all recipe:

• boost - apply defines to Boost::headers too #11217

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[conan-center-bot]

Failure in build 9 (b72e8e99f4875a27c15529cd96327ed19aa36353):

• boost/1.72.0@:
  Didn't run or was cancelled before finishing

• boost/1.79.0@:
  Didn't run or was cancelled before finishing

• boost/1.70.0@:
  An unexpected error happened and has been reported

• boost/1.78.0@:
  Didn't run or was cancelled before finishing

• boost/1.69.0@:
  Didn't run or was cancelled before finishing

• boost/1.75.0@:
  Didn't run or was cancelled before finishing

• boost/1.74.0@:
  Didn't run or was cancelled before finishing

• boost/1.71.0@:
  Didn't run or was cancelled before finishing

• boost/1.76.0@:
  Didn't run or was cancelled before finishing

• boost/1.73.0@:
  Didn't run or was cancelled before finishing

• boost/1.77.0@:
  Didn't run or was cancelled before finishing

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