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

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.

recipes/boost/all/conandata.yml

@@ -276,3 +276,5 @@ patches:
       base_path: "source_subfolder"
     - patch_file: "patches/1.79.0-0001-json-array-erase-relocate.patch"
       base_path: "source_subfolder"
+    - patch_file: "patches/1.79.0-smart_ptr_cw_ppc_msync.patch"
+      base_path: "source_subfolder"

recipes/boost/all/patches/1.79.0-smart_ptr_cw_ppc_msync.patch

@@ -0,0 +1,25 @@
+diff --git a/boost/smart_ptr/detail/sp_counted_base_cw_ppc.hpp b/boost/smart_ptr/detail/sp_counted_base_cw_ppc.hpp
+index 81387ce..58a69e6 100644
+--- a/boost/smart_ptr/detail/sp_counted_base_cw_ppc.hpp
++++ b/boost/smart_ptr/detail/sp_counted_base_cw_ppc.hpp
+@@ -35,8 +35,6 @@ BOOST_PRAGMA_MESSAGE("Using CodeWarrior/PowerPC sp_counted_base")
+
+ #endif
+
+-BOOST_SP_OBSOLETE()
+-
+ namespace boost
+ {
+
+@@ -64,7 +62,11 @@ inline long atomic_decrement( register long * pw )
+
+     asm
+     {
++#if defined(__PPCZen__) || defined(__PPCe500__) || defined(__PPCe500v2__)
++    msync
++#else
+     sync
++#endif
+
+ loop:
+