Revert "Remove telephony support for car builds."

This reverts commit e10b8dbbdcf75e90a811c4299d49698d56960fed.

Bug: 139484721
Bug: 139551240
Test: manual verification

Change-Id: Ie10bec490dc00f12dbb3580f9993a444afbdb83d
diff --git a/car_product/build/car.mk b/car_product/build/car.mk
index d170e8a..999bbff 100644
--- a/car_product/build/car.mk
+++ b/car_product/build/car.mk
@@ -57,8 +57,6 @@
     ro.fw.mu.headless_system_user=true \
     config.disable_systemtextclassifier=true
 
-TARGET_NO_TELEPHONY := true
-
 # Overlay for Google network and fused location providers
 $(call inherit-product, device/sample/products/location_overlay.mk)
 $(call inherit-product-if-exists, frameworks/base/data/fonts/fonts.mk)