Code review pal

[JPeterMugaas]

No description provided.

[tregubovav-dev]

All PAL warning suspended with this PR are false-positive warnings.
However, there are a couple issues not related to PAL needs to be reviewed and resolved.
See comments below.

[tregubovav-dev]

I think this function needs additional failure checks:

function LoadCertificate(const AFileName: String): PX509;
var
  LM: TMemoryStream;   //PALOFF - Created and freed objects,  Local identifiers that possibly are set more than once without referencing in-between
  LB: PBIO;
begin
  LB:=nil;
  LM := TMemoryStream.Create;
  try
    LM.LoadFromFile(AFileName);
    LB := BIO_new_mem_buf(LM.Memory^, LM.Size); //BIO_new_mem_buf may return NULL value
    Result := PEM_read_bio_X509(LB, nil, nil, nil); //Is it safe to pass NULL BIO to this routine?
  finally
    BIO_free(LB);
    FreeAndNil(LM);
  end;
end;

[tregubovav-dev]

For example, the 'TaurusTLS_SSL_CTX_use_PrivateKey_file_PKCS12, TaurusTLS_unicode_X509_load_cert_file`, etc. include additional error control to avoid NULL-referenced BIO.

[tregubovav-dev]

method function TaurusTLS_unicode_X509_load_cert_crl_file:
Variable Linf can reach line 596 uninitialized.
It must be null-assigned explicitly in the beginning of method.