MAINTAINERS: extend memblock entry to include MM initialization

and add mm/mm_init.c to memblock entry in MAINTAINERS

Link: https://lkml.kernel.org/r/20230321170513.2401534-15-rppt@kernel.orgSigned-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Doug Berger <opendmb@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

MAINTAINERS

@@ -13368,13 +13368,14 @@ F:	arch/powerpc/include/asm/membarrier.h
 F:	include/uapi/linux/membarrier.h
 F:	kernel/sched/membarrier.c
 
-MEMBLOCK
+MEMBLOCK AND MEMORY MANAGEMENT INITIALIZATION
 M:	Mike Rapoport <rppt@kernel.org>
 L:	linux-mm@kvack.org
 S:	Maintained
 F:	Documentation/core-api/boot-time-mm.rst
 F:	include/linux/memblock.h
 F:	mm/memblock.c
+F:	mm/mm_init.c
 F:	tools/testing/memblock/
 
 MEMORY CONTROLLER DRIVERS