unix: add fanotify API on Linux

This teaches unix/mksyscall.go about mapping uint64 to syscall
arguments, similar to existing handling of int64.

Change-Id: I536b4b09bbf6a8e3016565a4a04d2b9d32cbc624
Reviewed-on: https://go-review.googlesource.com/c/164664
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>

unix/mkerrors.sh

@@ -192,6 +192,7 @@ struct ltchars {
 #include <linux/if_packet.h>
 #include <linux/if_addr.h>
 #include <linux/falloc.h>
+#include <linux/fanotify.h>
 #include <linux/filter.h>
 #include <linux/fs.h>
 #include <linux/kexec.h>
@@ -501,6 +502,7 @@ ccflags="$@"
 		$2 !~ "WMESGLEN" &&
 		$2 ~ /^W[A-Z0-9]+$/ ||
 		$2 ~/^PPPIOC/ ||
+		$2 ~ /^FAN_|FANOTIFY_/ ||
 		$2 ~ /^BLK[A-Z]*(GET$|SET$|BUF$|PART$|SIZE)/ {printf("\t%s = C.%s\n", $2, $2)}
 		$2 ~ /^__WCOREFLAG$/ {next}
 		$2 ~ /^__W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", substr($2,3), $2)}