docs/vm: rename documentation files to .rst

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index e96adcb..f53e506 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -584,7 +584,7 @@
 	  Say Y to support efficient handling of discontiguous physical memory,
 	  for architectures which are either NUMA (Non-Uniform Memory Access)
 	  or have huge holes in the physical address space for other reasons.
-	  See <file:Documentation/vm/numa> for more.
+	  See <file:Documentation/vm/numa.rst> for more.
 
 source "mm/Kconfig"
 
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index bbe12a0..3ac9bf4 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -397,7 +397,7 @@
 	  Say Y to support efficient handling of discontiguous physical memory,
 	  for architectures which are either NUMA (Non-Uniform Memory Access)
 	  or have huge holes in the physical address space for other reasons.
- 	  See <file:Documentation/vm/numa> for more.
+	  See <file:Documentation/vm/numa.rst> for more.
 
 config ARCH_FLATMEM_ENABLE
 	def_bool y
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 8128c3b..4562810 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2551,7 +2551,7 @@
 	  Say Y to support efficient handling of discontiguous physical memory,
 	  for architectures which are either NUMA (Non-Uniform Memory Access)
 	  or have huge holes in the physical address space for other reasons.
-	  See <file:Documentation/vm/numa> for more.
+	  See <file:Documentation/vm/numa.rst> for more.
 
 config ARCH_SPARSEMEM_ENABLE
 	bool
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd..f8c0f10 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -880,7 +880,7 @@
 	  page-based protections, but without requiring modification of the
 	  page tables when an application changes protection domains.
 
-	  For details, see Documentation/vm/protection-keys.txt
+	  For details, see Documentation/vm/protection-keys.rst
 
 	  If unsure, say y.