kinect_fetch_fw: mention that p7zip-full >= 9.20 is needed

With earlier versions the firmware cannot be extracted from the .msi
file.

diff --git a/kinect_fetch_fw b/kinect_fetch_fw
index a358327..28a9fe7 100755 (executable)
--- a/kinect_fetch_fw
+++ b/kinect_fetch_fw
@@ -12,6 +12,9 @@
 #
 # wget and 7z from p7zip-full are needed, they can be installed with
 #   sudo aptitude install wget p7zip-full
+#
+# NOTE: p7zip-full >= 9.20 is required in order to extract .msi files
+#       correctly
 
 set -e