Fix is_remote check in gdb.base/remote.exp

1. Otherwise, when the native-gdbserver board stops setting is_remote,
   this test would stop running there.

2. Makes the test run with --target_board=native-extended-gdbserver
   too.

gdb/testsuite/ChangeLog:
2017-10-13  Pedro Alves  <palves@redhat.com>

	* gdb.base/remote.exp: Check gdb_protocol instead of is_remote.
	(top level): Add comment.

1 files changed, 7 insertions, 4 deletions

diff --git a/gdb/testsuite/gdb.base/remote.exp b/gdb/testsuite/gdb.base/remote.exp
index db6fc00..2f3ede1 100644
--- a/gdb/testsuite/gdb.base/remote.exp
+++ b/gdb/testsuite/gdb.base/remote.exp
@@ -13,10 +13,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-
-
-# test only on a remote target board
-if {! [is_remote target]} {
+# Test only on boards that actually use the remote protocol.
+if {[target_info gdb_protocol] != "remote"
+    && [target_info gdb_protocol] != "extended-remote"} {
     return
 }
 
@@ -103,6 +102,10 @@ proc gdb_load_timed {executable class writesize} {
     pass $test
 }
 
+# These download tests won't actually download anything on !is_remote
+# target boards, but we run them anyway because it's simpler, and
+# harmless.
+
 # Typically about 400-1 bytes can be downloaded
 gdb_load_timed $binfile "limit" 398
 gdb_load_timed $binfile "limit" 400