* c-tree.h (struct c_declspecs): Remove typedef_decl. Add
typedef_p and typedef_signed_p.
* c-decl.c (shadow_tag_warned): Check typedef_p, not typedef_decl.
(grokdeclarator): Don't use typedef_decl for warn_deprecated_use.
Check typedef_p and typedef_signed_p, not typedef_decl.
(grokfield): Check typedef_p, not typedef_decl.
(build_null_declspecs): Initialize typedef_p and typedef_signed_p,
not typedef_decl.
(declspecs_add_type): Set typedef_p and typedef_signed_p, not
typedef_decl.