j5lte: Add board flag to enable 'sms not sent' fix

Change-Id: Iee32c1ae7d9eb74ceda0d790f7bc0e9629d10a81
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 7b9114e..5381d49 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -15,3 +15,4 @@
 
 # RIL
 SIM_COUNT := 2
+BOARD_GLOBAL_CFLAGS += -DRIL_FIX_SMS_NOT_SENT_ERR