Add BUILD_BROKEN_ENFORCE_SYSPROP_OWNER

In terms of sepolicy rules, every property should have an apporpriate
owner attribute, which can be one of: system_property_type,
product_property_type, or vendor_property_type. This will be enforced
for devices launching with S or later. Devices launching with R or
eariler can relax this by setting following under BoardConfig.mk:

BUILD_BROKEN_ENFORCE_SYSPROP_OWNER := true

See system/sepolicy/public/te_macros for more details.

Bug: 131162102
Test: system/sepolicy/tools/build_policies.sh
Change-Id: Iee05fc15beac1ccf61da4ea901a85b9d4068e0ca