Add ro.vendor.build.fingerprint_has_digest to property context

This property indicates if the new fingerprint format is in use.
It's read by VTS to put the correct fingerprint in test report.

Bug: 188824341
Test: boot the device, check build prop
Change-Id: I2694d613e8d91d355506a4c7aaad4bdc191a800a
diff --git a/private/property_contexts b/private/property_contexts
index 3e4c19b..10e7c41 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -830,6 +830,7 @@
 ro.vendor.build.date                        u:object_r:build_vendor_prop:s0 exact string
 ro.vendor.build.date.utc                    u:object_r:build_vendor_prop:s0 exact int
 ro.vendor.build.fingerprint                 u:object_r:build_vendor_prop:s0 exact string
+ro.vendor.build.fingerprint_has_digest      u:object_r:build_vendor_prop:s0 exact bool
 ro.vendor.build.id                          u:object_r:build_vendor_prop:s0 exact string
 ro.vendor.build.tags                        u:object_r:build_vendor_prop:s0 exact string
 ro.vendor.build.type                        u:object_r:build_vendor_prop:s0 exact string