printflags: add printflags to PRODUCT_PACKAGES

Include the printflags device tool in the system image by default.

Bug: 301547297
Test: adb shell printflags
Change-Id: I3b2d71c89742bd389f6cafff8d8ab25fb81c7b00
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index f8dbafd..29e4ecd 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -235,6 +235,7 @@
     pm \
     pppd \
     preinstalled-packages-platform.xml \
+    printflags \
     privapp-permissions-platform.xml \
     prng_seeder \
     racoon \