FreeBSD patch

[yurivict]

Please apply this patch:

--- CMakeLists.txt.orig 2019-05-23 06:02:35 UTC
+++ CMakeLists.txt
@@ -86,7 +86,7 @@ if (${CMAKE_SYSTEM_NAME} STREQUAL Windows)
                source/msw/image.c
                source/msw/window.c)
        set(BUILD_GUI 1)
-elseif (${CMAKE_SYSTEM_NAME} STREQUAL Linux)
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL Linux OR ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD|DragonFly")
        list(APPEND SOURCES
                source/linux/l1tf.c
                source/linux/meltdown.c