* commons/common2.ml: put back old behavior for filename_of_dbe_noext

so xxx.root.c is analyzed as a .c file, not a .root.c file. Will have problem
again with .md5sum.tos.h files, but have to find another way to fix thoses
(e.g. by fixing syncweb to generate different filenames)
* lang_c/analyze/graph_code_c.ml: todos
* lang_c/parsing/lib_parsing_c.ml: todos
* lang_c/parsing/ast_c.ml: add expr for TArray, otherwise deadcode FPs on constants