rust: Fixup rust directiories to use direct link, not symlink

Background:
* We want to remove the symlink at some point. Go ahead and remove the
  symlink usage.

Bug: 394231854
Test: Builds
Change-Id: I2ad96bbe6de91c3b21c6dfa3eb613854d311b3cf
Signed-off-by: Donnie Pollitz <donpollitz@google.com>