a32: Disable serial console notification

Google added a check for this prop in R, and if it's running it will show a notification about it that it's impacting performance.
Why it's not disabled by default I don't know, so just force disable it here.

device.mk

@@ -295,6 +295,7 @@ PRODUCT_PACKAGES += \
     init.recovery.mt6768.rc \
     init.recovery.mt6769t.rc \
     init.recovery.samsung.rc \
+    init.target.rc \
     meta_init.connectivity.common.rc \
     meta_init.connectivity.rc \
     meta_init.modem.rc \

rootdir/Android.bp

@@ -105,6 +105,13 @@ prebuilt_etc {
     vendor: true,
 }
 
+prebuilt_etc {
+    name: "init.target.rc",
+    src: "etc/init.target.rc",
+    sub_dir: "init",
+    system_ext_specific: true,
+}
+
 prebuilt_etc {
     name: "init_connectivity.rc",
     src: "etc/init_connectivity.rc",

rootdir/etc/init.target.rc

@@ -0,0 +1,2 @@
+on boot
+    stop console