cmake: remove spurious UNIX_SYS in dep_option
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3405baf..f5a8007 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -439,7 +439,7 @@ dep_option(SDL_ARTS_SHARED "Dynamically load aRts audio support" ON "SDL
set_option(SDL_NAS "Support the NAS audio API" ${UNIX_SYS})
dep_option(SDL_NAS_SHARED "Dynamically load NAS audio support" ON "SDL_NAS" OFF)
set_option(SDL_SNDIO "Support the sndio audio API" ${UNIX_SYS})
-dep_option(SDL_SNDIO_SHARED "Dynamically load the sndio audio API" ${UNIX_SYS} ON "SDL_SNDIO" OFF)
+dep_option(SDL_SNDIO_SHARED "Dynamically load the sndio audio API" ON "SDL_SNDIO" OFF)
set_option(SDL_FUSIONSOUND "Use FusionSound audio driver" OFF)
dep_option(SDL_FUSIONSOUND_SHARED "Dynamically load fusionsound audio support" ON "SDL_FUSIONSOUND" OFF)
set_option(SDL_LIBSAMPLERATE "Use libsamplerate for audio rate conversion" ${UNIX_SYS})