Replace PATHFINDER_MACOS with __APPLE__

Author: errata-c

c/cbindgen.toml

@@ -5,10 +5,6 @@ header = """\
 #ifndef PF_PATHFINDER_H
 #define PF_PATHFINDER_H
 
-#if defined(__APPLE__)
-#define PATHFINDER_MACOS
-#endif
-
 #if defined(__APPLE__) && defined(__OBJC__)
 #include <QuartzCore/QuartzCore.h>
 #else
@@ -64,6 +60,6 @@ include = [
 "SVGScene" = "PFSVGScenePrivate"
 
 [defines]
-"target_os = macos" = "PATHFINDER_MACOS"
+"target_os = macos" = "__APPLE__"
 "feature = pf-text" = "PATHFINDER_TEXT"
 "feature = pf-gl" = "PATHFINDER_GL"