MAINTAINERS: Move linux-fpga tree to new location

Move the linux-fpga tree to new location at:
 git://git.kernel.org/pub/scm/linux/kernel/git/mdf/linux-fpga.gitSigned-off-by: Moritz Fischer <mdf@kernel.org>
Link: https://lore.kernel.org/r/20190725174517.10516-1-mdf@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MAINTAINERS

@@ -6339,7 +6339,7 @@ FPGA MANAGER FRAMEWORK
 M:	Moritz Fischer <mdf@kernel.org>
 L:	linux-fpga@vger.kernel.org
 S:	Maintained
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/atull/linux-fpga.git
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mdf/linux-fpga.git
 Q:	http://patchwork.kernel.org/project/linux-fpga/list/
 F:	Documentation/fpga/
 F:	Documentation/driver-api/fpga/