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/MAINTAINERS b/MAINTAINERS
index 63ae53c..59f7904 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -751,7 +751,7 @@
 F:	test/boot/
 
 BTRFS
-M:	Marek Behun <marek.behun@nic.cz>
+M:	Marek Behún <kabel@kernel.org>
 R:	Qu Wenruo <wqu@suse.com>
 L:	linux-btrfs@vger.kernel.org
 S:	Maintained
@@ -955,7 +955,7 @@
 
 KWBIMAGE / KWBOOT TOOLS
 M:	Pali Rohár <pali@kernel.org>
-M:	Marek Behún <marek.behun@nic.cz>
+M:	Marek Behún <kabel@kernel.org>
 M:	Stefan Roese <sr@denx.de>
 S:	Maintained
 T:	git https://source.denx.de/u-boot/custodians/u-boot-marvell.git