liblog: remove log_portability.h

__BEGIN_DECLS and __END_DECLS are all that are left, and I can compile
with using normal <sys/cdefs.h>, so hopefully we can remove this at
last.

Test: build
Change-Id: I6df7ef0da027bb91c98806e0f9661d7416ebaa5d
5 files changed
tree: 8ca18e36fe07d2c8840b02d09a6aa63b0077bafd
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/