IORequest::_CopyData(): Small optimization

If we're running in the context of the user team the I/O buffer belongs
to, we can use _CopySimple() as well.

src/system/kernel/device_manager/IORequest.cpp

@@ -1173,7 +1173,7 @@ IORequest::_CopyData(void* _buffer, off_t offset, size_t size, bool copyIn)
 	if (fBuffer->IsPhysical()) {
 		copyFunction = &IORequest::_CopyPhysical;
 	} else {
-		copyFunction = fBuffer->IsUser()
+		copyFunction = fBuffer->IsUser() && fTeam != team_get_current_team_id()
 			? &IORequest::_CopyUser : &IORequest::_CopySimple;
 	}