Fix dumping of heap memory.

After r.android.com/1288984 we started failing to dump memory contents
for heap addresses because the tag started causing any addresses to
fail this bounds check. Add an untag_address() call to the bounds check
so that the tag is ignored.

Bug: 154272452
Change-Id: I3a6d1a078b21871bd93164150a123549f83289f6