static analysis: Add suppression list for Cppcheck Static Code Analysis

The file tools/cppcheck_suppress_list.txt contains the list of warnings
we want to suppress when running Cppcheck.

Change-Id: I5998e58fccfe7706d16d59dcb4232f14ea0f0dd0
Signed-off-by: Raphael Gault <raphael.gault@arm.com>