Fix build on Mac

Recent libusb seems to have removed extra symlink `libusb-1.0/libusb.h`,
which breaks build on Mac.

TODO: consider always using `<libusb.h>`, but that would
put hard dependency on `pkg-config` usage.

Author: mvp

uhubctl.c

@@ -29,7 +29,7 @@
 #include <unistd.h>
 #endif
 
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(_WIN32)
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(_WIN32)
 #include <libusb.h>
 #else
 #include <libusb-1.0/libusb.h>