Update Cppcheck to v2.6.0 // Resolve #3942

HISTORY.rst

@@ -12,6 +12,7 @@ PlatformIO Core 5
 ~~~~~~~~~~~~~~~~~~
 
 - Allowed to override a default library builder via a new ``builder`` field in a ``build`` group of `library.json <https://docs.platformio.org/page/librarymanager/config.html#build>`__ manifest (`issue #3957 <https://github.com/platformio/platformio-core/issues/3957>`_)
+- Updated `Cppcheck <https://docs.platformio.org/page/plus/check-tools/cppcheck.html>`__ v2.6 with new checks, increased reliability of advanced addons (MISRA/CERT) and various improvements
 - Handle the "test" folder as a part of CLion project (`issue #4005 <https://github.com/platformio/platformio-core/issues/4005>`_)
 - Improved handling of a library root based on "Conan" or "CMake" build systems (`issue #3887 <https://github.com/platformio/platformio-core/issues/3887>`_)
 - Fixed a "KeyError: Invalid board option 'build.cpu'" when using a precompiled library with a board that does not have a CPU field in the manifest (`issue #4056 <https://github.com/platformio/platformio-core/issues/4056>`_)

platformio/__init__.py

@@ -51,7 +51,7 @@ __core_packages__ = {
     "contrib-pysite": "~2.%d%d.0" % (sys.version_info.major, sys.version_info.minor),
     "tool-unity": "~1.20500.0",
     "tool-scons": "~4.40200.0",
-    "tool-cppcheck": "~1.250.0",
+    "tool-cppcheck": "~1.260.0",
     "tool-clangtidy": "~1.120001.0",
     "tool-pvs-studio": "~7.14.0",
 }