EventLogChannel needs a message-compiler-generated pocomsg.h (and the Windows
Event Log message resource), which we do not build; it is unused by COOL/CODA.
Drop its include and its LoggingFactory registration on Windows so PocoFoundation
builds without pocomsg.h.  WindowsConsoleChannel (ConsoleChannel/ColorConsole-
Channel on Windows) is kept.  No-op on non-Windows (the code is in
POCO_OS_FAMILY_WINDOWS blocks).

--- a/Foundation/src/LoggingFactory.cpp
+++ b/Foundation/src/LoggingFactory.cpp
@@ -25,7 +25,6 @@
 #include "Poco/SyslogChannel.h"
 #endif
 #if defined(POCO_OS_FAMILY_WINDOWS)
-#include "Poco/EventLogChannel.h"
 #include "Poco/WindowsConsoleChannel.h"
 #endif
 #include "Poco/PatternFormatter.h"
@@ -108,9 +107,6 @@
 #endif
 #endif
 
-#if defined(POCO_OS_FAMILY_WINDOWS)
-	_channelFactory.registerClass("EventLogChannel"s, new Instantiator<EventLogChannel, Channel>);
-#endif
 
 	_formatterFactory.registerClass("PatternFormatter"s, new Instantiator<PatternFormatter, Formatter>);
 	_formatterFactory.registerClass("JSONFormatter"s, new Instantiator<JSONFormatter, Formatter>);