btl/ofi/Makefile.am: down with tabs!

Replace all tabs with spaces.  No code or logic changes.

Signed-off-by: Jeff Squyres <jsquyres@cisco.com>

opal/mca/btl/ofi/Makefile.am

@@ -9,7 +9,7 @@
 #                         University of Stuttgart.  All rights reserved.
 # Copyright (c) 2004-2005 The Regents of the University of California.
 #                         All rights reserved.
-# Copyright (c) 2009-2014 Cisco Systems, Inc.  All rights reserved.
+# Copyright (c) 2009-2019 Cisco Systems, Inc.  All rights reserved
 # Copyright (c) 2013      NVIDIA Corporation.  All rights reserved.
 # Copyright (c) 2017      IBM Corporation.  All rights reserved.
 # Copyright (c) 2018      Intel, inc. All rights reserved