treewide: Fix Marek's name and change my e-mail address

Fix diacritics in some instances of my name and change my e-mail address
to kabel@kernel.org.

Add corresponding .mailmap entries.

Signed-off-by: Marek BehĂșn <kabel@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5511231..ffd095f 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3,7 +3,7 @@
  * From linux/fs/btrfs/ctree.h
  *   Copyright (C) 2007,2008 Oracle.  All rights reserved.
  *
- * Modified in 2017 by Marek Behun, CZ.NIC, marek.behun@nic.cz
+ * Modified in 2017 by Marek Behún, CZ.NIC, kabel@kernel.org
  */
 
 #ifndef __BTRFS_CTREE_H__