Fix references to nommu-mmap.rst

nommu-mmap.rst was moved to Documentation/admin-guide/mm; this patch
updates the remaining stale references to Documentation/mm.

Fixes: 800c02f5d0 ("docs: move nommu-mmap.txt to admin-guide and rename to ReST")
Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200812092230.27541-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

init/Kconfig

@@ -1986,7 +1986,7 @@ config MMAP_ALLOW_UNINITIALIZED
 	  userspace.  Since that isn't generally a problem on no-MMU systems,
 	  it is normally safe to say Y here.
 
-	  See Documentation/mm/nommu-mmap.rst for more information.
+	  See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
 
 config SYSTEM_DATA_VERIFICATION
 	def_bool n

mm/Kconfig

@@ -383,7 +383,7 @@ config NOMMU_INITIAL_TRIM_EXCESS
 	  This option specifies the initial value of this option.  The default
 	  of 1 says that all excess pages should be trimmed.
 
-	  See Documentation/mm/nommu-mmap.rst for more information.
+	  See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
 
 config TRANSPARENT_HUGEPAGE
 	bool "Transparent Hugepage Support"

mm/nommu.c

@@ -5,7 +5,7 @@
  *  Replacement code for mm functions to support CPU's that don't
  *  have any form of memory management unit (thus no virtual memory).
  *
- *  See Documentation/mm/nommu-mmap.rst
+ *  See Documentation/admin-guide/mm/nommu-mmap.rst
  *
  *  Copyright (c) 2004-2008 David Howells <dhowells@redhat.com>
  *  Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com>