Address ld.config.txt comments.

Follow-up from:
https://android-review.googlesource.com/c/platform/art/+/879983

Test: m
Change-Id: I4b5601514aa1aae5bb48daeb58c4b183af4e8339
diff --git a/build/apex/ld.config.txt b/build/apex/ld.config.txt
index 9e709d8..0129772 100644
--- a/build/apex/ld.config.txt
+++ b/build/apex/ld.config.txt
@@ -29,11 +29,17 @@
 namespace.platform.link.default.shared_libs += libnativehelper.so
 namespace.platform.link.default.shared_libs += libnativeloader.so
 
+# Note that we don't need to link the default namespace with conscrypt:
+# the runtime Java code and binaries do not explicitly load native libraries
+# from it.
+
 ###############################################################################
 # "conscrypt" APEX namespace
 #
 # This namespace is for libraries within the conscrypt APEX.
 ###############################################################################
+
+# Keep in sync with conscrypt namespace in /system/etc/ld.config.txt.
 namespace.conscrypt.isolated = true
 namespace.conscrypt.visible = true