Add script to fix libusb on darwin

fixlibusb_darwin.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+function die {
+  echo "$@"
+  exit 1
+}
+
+FILE="$1"
+if [[ -z "$FILE" ]]; then
+  die "Usage: $0 <path to libusb.h>"
+fi
+
+if [[ $(gcc --version | grep -i "llvm") == "" ]]; then
+  die "Error: This change is unnecessary unless your gcc uses llvm"
+fi
+
+BACKUP="${FILE}.orig"
+if [[ -f "$BACKUP" ]]; then
+  die "It looks like you've already run this script ($BACKUP exists)"
+fi
+
+cp $FILE $BACKUP || die "Could not create backup"
+
+{
+  echo 'H'                                  # Turn on error printing
+  echo 'g/\[0\].*non-standard/s/\[0\]/[1]/' # Use [1] instead of [0] so the size is unambiguous
+  echo 'g/\[.\].*non-standard/p'            # Print the lines changed
+  echo 'w'                                  # Write output
+} | ed $FILE