gdb: ARC version is based on GDB 8.0, needs C++11 support

The special gdb version used for ARC is based on GDB 8.0, so it needs
C++11 support.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/gdb/Config.in.host

@@ -82,6 +82,7 @@ config BR2_PACKAGE_GDB_NEEDS_CXX11
 	default y if !BR2_PACKAGE_HOST_GDB
 	default y if BR2_GDB_VERSION_8_0
 	default y if BR2_GDB_VERSION_8_1
+	default y if BR2_arc
 
 # If cross-gdb is not enabled, the latest working version is chosen.
 config BR2_GDB_VERSION