beyondx: use correct default network mode (5G+4G)

Change-Id: I2b6d81ccd4d9cb9fdd28ca9f0fe9b8ae3dd9b25d
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 1dcbf76..40ee2ce 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -33,3 +33,6 @@
 
 ### VENDOR SECURITY PATCH DATE
 VENDOR_SECURITY_PATCH := 2021-04-01
+
+### VENDOR PROPS
+TARGET_VENDOR_PROP += $(DEVICE_PATH)/vendor.prop
diff --git a/vendor.prop b/vendor.prop
new file mode 100644
index 0000000..7ffefc0
--- /dev/null
+++ b/vendor.prop
@@ -0,0 +1,2 @@
+### RIL
+ro.telephony.default_network=26,9