liblog: run liblog#enoent only as root

Previously this test would rely on ro.debuggable being true, but there
are now some circumstances where ro.debuggable is true, yet `su` does
not exist.  Therefore we only run this test when it is root.

Also simplify some of the test macros.

Bug: 140446213
Test: passes as root, skips as non-root
Change-Id: I0651963d5c7d4f5308989ab6b04aab1042094e5a
1 file changed
tree: bc60e50b495a517b3ebb10470ac80b2f724a9a5a
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/