fix NOR flash regression

When factoring the bank setup command into flash_bank_add(), I forgot
to include a call to the new helper.

src/flash/nor/tcl.c

@@ -813,6 +813,8 @@ COMMAND_HANDLER(handle_flash_bank_command)
 		return retval;
 	}
 
+	flash_bank_add(c);
+
 	return ERROR_OK;
 
 }