Regenerate NOTICE files.

Also clean up some obsolete cruft.

Change-Id: Iec3b36f6607f7a08b72de99294ed5b6cd910dd5f
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index dc139bd..2a25618 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -25,7 +25,10 @@
 #      - additionally, if the syscall number is different amoung ARM, and x86, MIPS use:
 #        return_type funcname[:syscall_name](parameters) arm_number,x86_number,mips_number
 #
-# the file is processed by a python script named gensyscalls.py
+# This file is processed by a python script named gensyscalls.py.
+#
+# The checksyscalls.py script can check that the syscall numbers here are
+# correct by comparing them to the numbers in the Linux kernel headers.
 #
 
 # process management