test: Add K210 PLL tests to sandbox defconfigs

This adds the unit test for the K210 PLL to the sandbox defconfigs.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/sandbox64_defconfig b/configs/sandbox64_defconfig
index 9a373ba..9cd7461 100644
--- a/configs/sandbox64_defconfig
+++ b/configs/sandbox64_defconfig
@@ -107,6 +107,8 @@
 CONFIG_BUTTON=y
 CONFIG_BUTTON_GPIO=y
 CONFIG_CLK=y
+CONFIG_CLK_K210=y
+CONFIG_CLK_K210_SET_RATE=y
 CONFIG_CPU=y
 CONFIG_DM_DEMO=y
 CONFIG_DM_DEMO_SIMPLE=y