sm7250-common: relax sysprop owner enforcement

Quoting commit afc09932f6fa07c5f6beffbcdc2bb4691e527321 in
system/sepolicy [1]:

"Devices launching with R or eariler can this by setting following
under BoardConfig.mk"

It is impractical to replace every prop definition from qcom to
vendor_property_type for old platforms like SDM845, so relax the
enforcement to avoid triggering millions of neverallows.

ref:
[1] afc09932f6

Signed-off-by: Chenyang Zhong <zhongcy95@gmail.com>

BoardConfigCommon.mk

@@ -16,6 +16,7 @@
 
 BUILD_BROKEN_DUP_RULES := true
 BUILD_BROKEN_ELF_PREBUILT_PRODUCT_COPY_FILES := true
+BUILD_BROKEN_ENFORCE_SYSPROP_OWNER := true
 
 BOARD_VENDOR := oneplus