docs/vm: zsmalloc.txt: convert to ReST format

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/vm/zsmalloc.txt

+.. _zsmalloc:
+
+========
 zsmalloc
---------
+========
 
 This allocator is designed for use with zram. Thus, the allocator is
 supposed to work well under low memory conditions. In particular, it
@@ -31,40 +34,49 @@ be mapped using zs_map_object() to get a usable pointer and subsequently
 unmapped using zs_unmap_object().
 
 stat
-----
+====
 
 With CONFIG_ZSMALLOC_STAT, we could see zsmalloc internal information via
-/sys/kernel/debug/zsmalloc/<user name>. Here is a sample of stat output:
+``/sys/kernel/debug/zsmalloc/<user name>``. Here is a sample of stat output::
 
-# cat /sys/kernel/debug/zsmalloc/zram0/classes
+ # cat /sys/kernel/debug/zsmalloc/zram0/classes
 
  class  size almost_full almost_empty obj_allocated   obj_used pages_used pages_per_zspage
-    ..
-    ..
+    ...
+    ...
      9   176           0            1           186        129          8                4
     10   192           1            0          2880       2872        135                3
     11   208           0            1           819        795         42                2
     12   224           0            1           219        159         12                4
-    ..
-    ..
+    ...
+    ...
+
 
+class
+	index
+size
+	object size zspage stores
+almost_empty
+	the number of ZS_ALMOST_EMPTY zspages(see below)
+almost_full
+	the number of ZS_ALMOST_FULL zspages(see below)
+obj_allocated
+	the number of objects allocated
+obj_used
+	the number of objects allocated to the user
+pages_used
+	the number of pages allocated for the class
+pages_per_zspage
+	the number of 0-order pages to make a zspage
 
-class: index
-size: object size zspage stores
-almost_empty: the number of ZS_ALMOST_EMPTY zspages(see below)
-almost_full: the number of ZS_ALMOST_FULL zspages(see below)
-obj_allocated: the number of objects allocated
-obj_used: the number of objects allocated to the user
-pages_used: the number of pages allocated for the class
-pages_per_zspage: the number of 0-order pages to make a zspage
+We assign a zspage to ZS_ALMOST_EMPTY fullness group when n <= N / f, where
 
-We assign a zspage to ZS_ALMOST_EMPTY fullness group when:
-      n <= N / f, where
-n = number of allocated objects
-N = total number of objects zspage can store
-f = fullness_threshold_frac(ie, 4 at the moment)
+* n = number of allocated objects
+* N = total number of objects zspage can store
+* f = fullness_threshold_frac(ie, 4 at the moment)
 
 Similarly, we assign zspage to:
-      ZS_ALMOST_FULL  when n > N / f
-      ZS_EMPTY        when n == 0
-      ZS_FULL         when n == N
+
+* ZS_ALMOST_FULL  when n > N / f
+* ZS_EMPTY        when n == 0
+* ZS_FULL         when n == N