patch 8.1.1231: asking about existing swap file unnecessarily

Problem:    Asking about existing swap file unnecessarily.
Solution:   When it is safe, delete the swap file.  Remove
            HAS_SWAP_EXISTS_ACTION, it is always defined. (closes #1237)
diff --git a/src/fileio.c b/src/fileio.c
index b301846..659878e 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -684,15 +684,13 @@
 #endif
     }
 
-#if defined(HAS_SWAP_EXISTS_ACTION)
-    /* If "Quit" selected at ATTENTION dialog, don't load the file */
+    // If "Quit" selected at ATTENTION dialog, don't load the file
     if (swap_exists_action == SEA_QUIT)
     {
 	if (!read_buffer && !read_stdin)
 	    close(fd);
 	return FAIL;
     }
-#endif
 
     ++no_wait_return;	    /* don't wait for return yet */