lava_helper_configs.py: Re-enable NXP board LAVA test

Since the blocked issue has been solved, reenable the LAVA test for the
LPCXpresso55s69 board.

Signed-off-by: Arthur She <arthur.she@linaro.org>
Change-Id: Ib904c93136d764c897151fc9c65676b39e0f3e30
diff --git a/lava_helper/lava_helper_configs.py b/lava_helper/lava_helper_configs.py
index fea1161..3896444 100644
--- a/lava_helper/lava_helper_configs.py
+++ b/lava_helper/lava_helper_configs.py
@@ -284,6 +284,7 @@
     "qemu_mps2_bl2": qemu_mps2_bl2,
     "musca_b1": musca_b1_bl2,
     "stm32l562e_dk": stm32l562e_dk,
+    "lpcxpresso55s69": lpcxpresso55s69,
     "psoc64": psoc64,
 }