Allow restart in gdbclient.

Switching from remote to extended-remote allows the program being
debugged to be restarted like a normal non-remote program.

Test: Used gdbclient debugging ICU things for a while, restarted often
Bug: None
Change-Id: Ia295749b9aa86727479d760d7c743f98a06fa6d4
diff --git a/scripts/gdbclient.py b/scripts/gdbclient.py
index 982ddc8..ff0ee40 100755
--- a/scripts/gdbclient.py
+++ b/scripts/gdbclient.py
@@ -192,7 +192,7 @@
   end_time = time.time() + timeout_seconds
   while True:
     try:
-      gdb.execute("target remote " + target)
+      gdb.execute("target extended-remote " + target)
       return True
     except gdb.error as e:
       time_left = end_time - time.time()