Online transfer: Do no longer force existence of local BIC code

The BIC code for SEPA transfer used to be mandantory, but turned optional
more recently and the local IBAN code is sufficient. Gnucash still
checked the local BIC code existence and forced the user to get it
from somewhere. This is no longer needed - local IBAN is enough.

gnucash/import-export/aqb/dialog-ab-trans.c

@@ -598,10 +598,8 @@ gnc_ab_trans_dialog_verify_values(GncABTransDialog *td)
     // Verify that we have a local IBAN and BIC
     if (gnc_ab_trans_isSEPA(td->trans_type))
     {
-        const char* localBIC = AB_Transaction_GetLocalBic(td->ab_trans);
         const char* localIBAN = AB_Transaction_GetLocalIban(td->ab_trans);
-        if (!localBIC || !localIBAN
-                || (strlen(localBIC) == 0) || (strlen(localIBAN) == 0))
+        if (!localIBAN || (strlen(localIBAN) == 0))
         {
             const char* localBankCode = AB_Transaction_GetLocalBankCode(td->ab_trans);
             const char* localAccountCode = AB_Transaction_GetLocalAccountNumber(td->ab_trans);