analyzer: fix Clang warnings

analyzer: fix Clang warnings

Fixes the following warnings:
gcc/analyzer/varargs.cc:655:8: warning: 'matches_call_types_p' overrides a member function but is not marked 'override' [-Winconsistent-missing-override]
gcc/analyzer/varargs.cc:707:50: warning: unused parameter 'cd' [-Wunused-parameter]
gcc/analyzer/varargs.cc:707:8: warning: 'matches_call_types_p' overrides a member function but is not marked 'override' [-Winconsistent-missing-override]

gcc/analyzer/ChangeLog:

	* varargs.cc: Fix Clang warnings.