MacPlatform: fix error that says @rpath/libhl.dylib is not found wh…

…en using HashLink nightly builds for HL/C

Added `@executable_path` to the rpath.

tools/platforms/MacPlatform.hx

@@ -214,7 +214,7 @@ class MacPlatform extends PlatformTarget
 				// compiler command with the `arch -x86_64` command.
 				// if we ever support ARM or Universal binaries, this will
 				// need to be handled differently.
-				var command = ["arch", "-x86_64", compiler, "-O3", "-o", executablePath, "-std=c11", "-I", Path.combine(targetDirectory, "obj"), Path.combine(targetDirectory, "obj/ApplicationMain.c")];
+				var command = ["arch", "-x86_64", compiler, "-O3", "-o", executablePath, "-std=c11", "-Wl,-rpath,@executable_path", "-I", Path.combine(targetDirectory, "obj"), Path.combine(targetDirectory, "obj/ApplicationMain.c")];
 				for (file in System.readDirectory(executableDirectory))
 				{
 					switch Path.extension(file)