Make static a const in SiStripFecCabling::fecs()

Silences Clang Static Analyzer warning.

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Fixed missing initialization of new member variable
Merge pull request #1571 from Dr15Jones/fixServiceThrowingExceptionAtEndEvent2

Multithreaded framework -- Fixed missing initialization of new member variable
Merge pull request #1532 from davidlt/clean-up-static-SiStripFecCabling.h

Multithreading fixes -- Make static a const in SiStripFecCabling::fecs()