MAINTAINERS: Remove Michal Marek from Kbuild maintainers

Remove Michal Marek from Kbuild maintainers as there is no response from him
since October 2017.  Add an entry for Michal in CREDITS.

Michal, thanks for maintaining Kbuild for almost eight years!
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Signed-off-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

CREDITS

@@ -2452,6 +2452,10 @@ S: 482 Shadowgraph Dr.
 S: San Jose, CA  95110
 S: USA
 
+N: Michal Marek
+E: michal.lkml@markovi.net
+D: Kbuild Maintainer 2009-2017
+
 N: Martin Mares
 E: mj@ucw.cz
 W: http://www.ucw.cz/~mj/

MAINTAINERS

@@ -11092,7 +11092,6 @@ F:	fs/autofs/
 
 KERNEL BUILD + files below scripts/ (unless maintained elsewhere)
 M:	Masahiro Yamada <masahiroy@kernel.org>
-M:	Michal Marek <michal.lkml@markovi.net>
 R:	Nathan Chancellor <nathan@kernel.org>
 R:	Nick Desaulniers <ndesaulniers@google.com>
 R:	Nicolas Schier <nicolas@fjasle.eu>