(RLaunch) Avoid unistd.h includes on MSVC

tools/retrolaunch/cd_detect.h

@@ -1,3 +1,7 @@
+#ifdef _WIN32
+#include <io.h>
+#else
 #include <unistd.h>
+#endif
 
 int detect_cd_game(const char* cue_path, char* game_name, size_t max_len);

tools/retrolaunch/main.c

@@ -1,4 +1,8 @@
+#ifdef _WIN32
+#include <io.h>
+#else
 #include <unistd.h>
+#endif
 #include <errno.h>
 #include <string.h>
 #include <stdlib.h>

tools/retrolaunch/parser.h

@@ -1,4 +1,8 @@
+#ifdef _WIN32
+#include <io.h>
+#else
 #include <unistd.h>
+#endif
 
 #define MAX_TOKEN_LEN 255