ipconfig: add nameserver IPs to kernel-parameter ip=

On small systems (e.g. embedded ones) IP addresses are often configured
by bootloaders and get assigned to kernel via parameter "ip=".  If set to
"ip=dhcp", even nameserver entries from DHCP daemons are handled. These
entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf.

To configure nameservers for networks without DHCP, this patch adds option
<dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.

Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com>
Tested-by: Jan Weitzel <j.weitzel@phytec.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt
index ffdd9d86..2d66ed6 100644
--- a/Documentation/filesystems/nfs/nfsroot.txt
+++ b/Documentation/filesystems/nfs/nfsroot.txt
@@ -78,7 +78,8 @@
 			flags		= hard, nointr, noposix, cto, ac
 
 
-ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
+ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>:
+   <dns0-ip>:<dns1-ip>
 
   This parameter tells the kernel how to configure IP addresses of devices
   and also how to set up the IP routing table. It was originally called
@@ -158,6 +159,13 @@
 
                 Default: any
 
+  <dns0-ip>	IP address of first nameserver.
+		Value gets exported by /proc/net/pnp which is often linked
+		on embedded systems by /etc/resolv.conf.
+
+  <dns1-ip>	IP address of secound nameserver.
+		Same as above.
+
 
 nfsrootdebug