Make thirty functions static to reduce binary size

If any of those functions should be (unused) API functions,
they can easily be turned back once really needed.

Detected using a new cppcheck check that
uses the internal symbol database to catch
functions that are only used in the current file.

Change-Id: Ic2b1e5b8020b76397f11cefc4e205f3b7ac1f184
10 files changed