core: Add Insurgency support for amd64 Windows (#1295)

* Add basic Insurgency support on Windows x64

This allows SourceMod to load on x64 Insurgency. There are still a lot of variable truncation warnings that have to be dealt with.

* Fix 32bit builds

* Compile MySQL extension as well

The hack for __iob_func being removed from the core runtime, but required by the old mysql we're building against can be simplified a lot due to the `_ReturnAddress` intrinsic available since MSVC 2015.

* Don't include the offset we want to extract in the signature

extensions/mysql/mysql/MyDatabase.cpp

@@ -185,7 +185,7 @@ bool MyDatabase::DoSimpleQuery(const char *query)
 
 IQuery *MyDatabase::DoQuery(const char *query)
 {
-	if (mysql_real_query(m_mysql, query, strlen(query)) != 0)
+	if (mysql_real_query(m_mysql, query, static_cast<unsigned long>(strlen(query))) != 0)
 	{
 		return NULL;
 	}
@@ -216,7 +216,7 @@ bool MyDatabase::DoSimpleQueryEx(const char *query, size_t len)
 
 IQuery *MyDatabase::DoQueryEx(const char *query, size_t len)
 {
-	if (mysql_real_query(m_mysql, query, len) != 0)
+	if (mysql_real_query(m_mysql, query, static_cast<unsigned long>(len)) != 0)
 	{
 		return NULL;
 	}
@@ -258,7 +258,7 @@ IPreparedQuery *MyDatabase::PrepareQuery(const char *query, char *error, size_t
 		return NULL;
 	}
 
-	if (mysql_stmt_prepare(stmt, query, strlen(query)) != 0)
+	if (mysql_stmt_prepare(stmt, query, static_cast<unsigned long>(strlen(query))) != 0)
 	{
 		if (error)
 		{

extensions/mysql/mysql/MyDriver.cpp

@@ -224,7 +224,7 @@ void MyDriver::ShutdownThreadSafety()
 	mysql_thread_end();
 }
 
-unsigned int strncopy(char *dest, const char *src, size_t count)
+size_t strncopy(char *dest, const char *src, size_t count)
 {
 	if (!count)
 	{

extensions/mysql/mysql/MyDriver.h

@@ -88,6 +88,6 @@ private:
 
 extern MyDriver g_MyDriver;
 
-unsigned int strncopy(char *dest, const char *src, size_t count);
+size_t strncopy(char *dest, const char *src, size_t count);
 
 #endif //_INCLUDE_SM_MYSQL_DRIVER_H_