misc: Document arm_control and that it shouldn't be used (raspberrypi#830)

kees · JamesH65 · commit b577ce35ea40 · 2018-02-28T12:39:01.000Z
* misc: Document arm_control and that it shouldn't be used

Include this for completeness and provide a note on avoiding it.

* Update misc.md
diff --git a/configuration/config-txt/misc.md b/configuration/config-txt/misc.md
@@ -11,6 +11,10 @@ The [warning symbols](../warning-icons.md) can be disabled using this option, al
 
 Sets the Videocore logging level. The value is a Videocore-specific bitmask.
 
+## arm_control
+
+Sets board-specific control bits. **NOTE:** This option is deprecated in favour of using the `arm_64bit` command to set the 64-bit boot control bit (arm_control=`0x200`).
+
 ## arm_64bit
 
 If set, this forces the kernel loading system to assume a 64-bit kernel.
