Remove ro.bootimage.* sysprops

ro.bootimage.build.date.* are not used anywhere.
ro.bootimage.build.fingerprint was used in the recovery mode, which has
now been switched to ro.build.fingerprint.

Bug: 117892318
Test: m
Change-Id: I3776c4154f86ddb908b24c6899037c6a7df037df
diff --git a/core/sysprop.mk b/core/sysprop.mk
index 9bf45e7..aa8a6ca 100644
--- a/core/sysprop.mk
+++ b/core/sysprop.mk
@@ -289,12 +289,6 @@
 	$(hide) rm -f $@ && touch $@
 	$(hide) $(call generate-common-build-props,vendor,$@)
 	$(hide) echo "#" >> $@; \
-	        echo "# BOOTIMAGE_BUILD_PROPERTIES" >> $@; \
-	        echo "#" >> $@;
-	$(hide) echo ro.bootimage.build.date=`$(DATE_FROM_FILE)`>>$@
-	$(hide) echo ro.bootimage.build.date.utc=`$(DATE_FROM_FILE) +%s`>>$@
-	$(hide) echo ro.bootimage.build.fingerprint="$(BUILD_FINGERPRINT_FROM_FILE)">>$@
-	$(hide) echo "#" >> $@; \
 	        echo "# ADDITIONAL VENDOR BUILD PROPERTIES" >> $@; \
 	        echo "#" >> $@;
 ifdef property_overrides_split_enabled