Fix guard context for forward declarations in asn split

Three fixes for guard-context correctness in the ASN.1 code split:

1. Strip WOLFSSL_ASN_ORIG_INCLUDED from forward declaration wrappers.
   The file-guard was being applied to fwd decls in asn.c, but at the
   fwd-decl site that macro is not yet defined, so #ifndef ... #else
   inverted the condition and hid all declarations.

2. Add outer feature guard tracking. Large feature sections (HAVE_OCSP,
   HAVE_CRL, WOLFSSL_CERT_GEN, etc.) that span many functions in asn.c
   are now tracked and re-emitted around the corresponding blocks in
   asn_orig.c, fixing 'unknown type name' errors in minimal builds.

3. Collect multi-line #if continuations in the outer guard map so that
   full guard conditions (e.g. #if !defined(NO_RSA) && \ continued
   across lines) are stored and compared as complete strings, preventing
   duplicate guard emission.

Both modes build and pass tests (5 PASS, 0 FAIL each):
  ./configure --enable-asn=original && make check
  ./configure && make check

Author: dgarske