arm64: defconfig: Enable configs for Toshiba Visconti

Enable support for the Toshiba Visconti SoCs.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: NPunit Agrawal <punit1.agrawal@toshiba.co.jp>

arch/arm64/configs/defconfig

@@ -57,6 +57,7 @@ CONFIG_ARCH_THUNDER=y
 CONFIG_ARCH_THUNDER2=y
 CONFIG_ARCH_UNIPHIER=y
 CONFIG_ARCH_VEXPRESS=y
+CONFIG_ARCH_VISCONTI=y
 CONFIG_ARCH_XGENE=y
 CONFIG_ARCH_ZX=y
 CONFIG_ARCH_ZYNQMP=y