added dxt.c for linux

Makefile

@@ -27,7 +27,7 @@ STD = src/std/array.o src/std/buffer.o src/std/bytes.o src/std/cast.o src/std/da
 
 HL = src/code.o src/jit.o src/main.o src/module.o src/debugger.o
 
-FMT = libs/fmt/fmt.o libs/fmt/sha1.o include/mikktspace/mikktspace.o libs/fmt/mikkt.o
+FMT = libs/fmt/fmt.o libs/fmt/sha1.o include/mikktspace/mikktspace.o libs/fmt/mikkt.o libs/fmt/dxt.o
 
 SDL = libs/sdl/sdl.o libs/sdl/gl.o
 

libs/fmt/CMakeLists.txt

@@ -113,6 +113,7 @@ if(WIN32)
         ${INCLUDES_BASE_DIR}/vorbis/window.c
         fmt.c
         sha1.c
+		dxt.c
     )
 else()
     find_package(ZLIB REQUIRED)