Rename product_services to system_ext

Update adb, fastboot and mount point

Bug: 134359158
Test: build and check if system_ext.img can be flashed
Change-Id: I6219f72242c5fe42a508008c0b1fd218d74da5b6
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index f084cd2..246f9ac 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -113,10 +113,10 @@
 else
   LOCAL_POST_INSTALL_CMD += ; ln -sf /system/product $(TARGET_ROOT_OUT)/product
 endif
-ifdef BOARD_USES_PRODUCT_SERVICESIMAGE
-  LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/product_services
+ifdef BOARD_USES_SYSTEM_EXTIMAGE
+  LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/system_ext
 else
-  LOCAL_POST_INSTALL_CMD += ; ln -sf /system/product_services $(TARGET_ROOT_OUT)/product_services
+  LOCAL_POST_INSTALL_CMD += ; ln -sf /system/system_ext $(TARGET_ROOT_OUT)/system_ext
 endif
 ifdef BOARD_USES_METADATA_PARTITION
   LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/metadata