feat(log4cxx): add 'events_at_exit' variant

packages/log4cxx/package.py

@@ -22,6 +22,10 @@ class Log4cxx(CMakePackage):
     version("0.12.0", sha256="bd5b5009ca914c8fa7944b92ea6b4ca6fb7d146f65d526f21bf8b3c6a0520e44")
 
     variant("cxxstd", default="17", description="C++ standard", values=("11", "17"), multi=False)
+    variant("events_at_exit",
+            default=False,
+            description="Enable to use logging during the application termination"
+            )
 
     depends_on("cmake@3.13:", type="build")
 
@@ -35,4 +39,5 @@ class Log4cxx(CMakePackage):
         return [
             self.define_from_variant("CMAKE_CXX_STANDARD", "cxxstd"),
             self.define("BUILD_TESTING", "off"),
+            self.define_from_variant("LOG4CXX_EVENTS_AT_EXIT", "events_at_exit"),
         ]