RFA: Recognize 'unknown host' errors when connecting to gdbserver

[Jim Blandy <jimb@codesourcery.com>]

This patch makes the GDB test suite not hang when trying to connect to
gdbserver.  Granted, looking up 'localhost' shouldn't give an error;
why that happens on my machine is a separate question.

gdb/testsuite/ChangeLog:
2007-12-20  Jim Blandy  <jimb@codesourcery.com>

	* lib/gdbserver-support.exp (gdb_target_cmd): Recognize 'unknown
	host' errors.
	* lib/mi-support.exp (mi_gdb_target_cmd): Same.

diff -r 69e7c25fdf59 gdb/testsuite/lib/gdbserver-support.exp
--- a/gdb/testsuite/lib/gdbserver-support.exp	Wed Dec 19 14:27:19 2007 -0800
+++ b/gdb/testsuite/lib/gdbserver-support.exp	Thu Dec 20 11:14:56 2007 -0800
@@ -52,6 +52,9 @@ proc gdb_target_cmd { targetname serialp
 		send_gdb "y\n"
 		exp_continue
 	    }
+            -re "unknown host.*$gdb_prompt" {
+                verbose "Couldn't look up $serialport"
+            }
 	    -re "Couldn't establish connection to remote.*$gdb_prompt $" {
 		verbose "Connection failed"
 	    }
diff -r 69e7c25fdf59 gdb/testsuite/lib/mi-support.exp
--- a/gdb/testsuite/lib/mi-support.exp	Wed Dec 19 14:27:19 2007 -0800
+++ b/gdb/testsuite/lib/mi-support.exp	Thu Dec 20 11:14:56 2007 -0800
@@ -332,6 +332,9 @@ proc mi_gdb_target_cmd { targetname seri
 		verbose "Set target to $targetname";
 		return 0;
 	    }
+            -re "unknown host.*$mi_gdb_prompt" {
+                verbose "Couldn't look up $serialport"
+            }
 	    -re "Couldn't establish connection to remote.*$mi_gdb_prompt$" {
 		verbose "Connection failed";
 	    }