MAINTAINERS: Add myself as reviewer instead of Naga

Naga no longer works for AMD/Xilinx and there is no activity from him to
continue to maintain Xilinx related drivers. Add myself instead to be kept
in loop if there is any need for testing.

Signed-off-by: Michal Simek <[email protected]>
Signed-off-by: Miquel Raynal <[email protected]>
[<[email protected]>: Manually apply on top of the latest -rc which
                              where the MAINTAINERS file got sorted]
Link: https://lore.kernel.org/linux-mtd/06df49c300c53a27423260e99acc217b06d4e588.1684827820.git.michal.simek@amd.com

Author: michalsimek

MAINTAINERS

@@ -1600,7 +1600,7 @@ F:	drivers/media/i2c/ar0521.c
 
 ARASAN NAND CONTROLLER DRIVER
 M:	Miquel Raynal <[email protected]>
-M:	Naga Sureshkumar Relli <nagasure@xilinx.com>
+R:	Michal Simek <michal.simek@amd.com>
 L:	[email protected]
 S:	Maintained
 F:	Documentation/devicetree/bindings/mtd/arasan,nand-controller.yaml
@@ -1763,15 +1763,15 @@ F:	include/linux/amba/mmci.h
 
 ARM PRIMECELL PL35X NAND CONTROLLER DRIVER
 M:	Miquel Raynal <[email protected]>
-M:	Naga Sureshkumar Relli <nagasure@xilinx.com>
+R:	Michal Simek <michal.simek@amd.com>
 L:	[email protected]
 S:	Maintained
 F:	Documentation/devicetree/bindings/mtd/arm,pl353-nand-r2p1.yaml
 F:	drivers/mtd/nand/raw/pl35x-nand-controller.c
 
 ARM PRIMECELL PL35X SMC DRIVER
 M:	Miquel Raynal <[email protected]>
-M:	Naga Sureshkumar Relli <nagasure@xilinx.com>
+R:	Michal Simek <michal.simek@amd.com>
 L:	[email protected] (moderated for non-subscribers)
 S:	Maintained
 F:	Documentation/devicetree/bindings/memory-controllers/arm,pl35x-smc.yaml