[pushed] Fix gdb.base/valgrind-infcall.exp with the native-extended-gdbserver board

[Pedro Alves <palves at redhat dot com>]

This test fails with --target_board=native-extended-gdbserver because
it misses the usual "disconnect":

 (gdb)  target remote | /usr/lib64/valgrind/../../bin/vgdb --pid=30454
 Already connected to a remote target.  Disconnect? (y or n) n
 Still connected.
 (gdb) FAIL: gdb.base/valgrind-infcall.exp: target remote for vgdb (got interactive prompt)

gdb/testsuite/ChangeLog:
2015-08-06  Pedro Alves  <palves@redhat.com>

	* gdb.base/valgrind-infcall.exp: Issue a "disconnect".
---
 gdb/testsuite/ChangeLog                     | 4 ++++
 gdb/testsuite/gdb.base/valgrind-infcall.exp | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index eccdddb..e4be76e 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,9 @@
 2015-08-06  Pedro Alves  <palves@redhat.com>
 
+	* gdb.base/valgrind-infcall.exp: Issue a "disconnect".
+
+2015-08-06  Pedro Alves  <palves@redhat.com>
+
 	PR gdb/18749
 	* gdb.threads/process-dies-while-handling-bp.c: New file.
 	* gdb.threads/process-dies-while-handling-bp.exp: New file.
diff --git a/gdb/testsuite/gdb.base/valgrind-infcall.exp b/gdb/testsuite/gdb.base/valgrind-infcall.exp
index b835c67..6e2460b 100644
--- a/gdb/testsuite/gdb.base/valgrind-infcall.exp
+++ b/gdb/testsuite/gdb.base/valgrind-infcall.exp
@@ -83,6 +83,11 @@ unset_board_info fileid
 
 clean_restart $testfile
 
+# Make sure we're disconnected, in case we're testing with the
+# native-extended-gdbserver board, where gdb_start/gdb_load spawn
+# gdbserver and connect to it.
+gdb_test "disconnect" ".*"
+
 gdb_test "$vgdbcmd" " in \\.?_start .*" "target remote for vgdb"
 
 gdb_test "monitor v.set gdb_output" "valgrind output will go to gdb.*"
-- 
1.9.3