Add OpenBSD support

Add a requirements section to the man page which lists the needed access
permissions for each programmer.

This feature needs my pciutils/libpci 8/16-bit write emulation patch at
http://marc.info/?l=openbsd-ports&m=127780030728045 titled
[PATCH] Fix pciutils non-32bit PCI write on OpenBSD

Corresponding to flashrom svn r1067.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stuart Henderson <sthen@openbsd.org>
diff --git a/hwaccess.c b/hwaccess.c
index 85e13ed..3a61e60 100644
--- a/hwaccess.c
+++ b/hwaccess.c
@@ -57,6 +57,11 @@
 #endif
 		msg_perr("ERROR: Could not get I/O privileges (%s).\n"
 			"You need to be root.\n", strerror(errno));
+#if defined (__OpenBSD__)
+		msg_perr("Please set securelevel=-1 in /etc/rc.securelevel "
+			   "and reboot, or reboot into \n");
+		msg_perr("single user mode.\n");
+#endif
 		exit(1);
 	}
 #endif