new "stellaris recover" command

Stellaris chips have a procedure for restoring the chip to
what's effectively the "as-manufactured" state, with all the
non-volatile memory erased.  That includes all flash memory,
plus things like the flash protection bits and various control
words which can for example disable debugger access.  clearly,
this can be useful during development.

Luminary/TI provides an MS-Windows utility to perform this
procedure along with its Stellaris developer kits.  Now OpenOCD
users will no longer need to use that MS-Windows utility.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

doc/openocd.texi

@@ -4497,6 +4497,21 @@ flash bank stellaris 0 0 0 0 $_TARGETNAME
 @end example
 @end deffn
 
+@deffn Command {stellaris recover bank_id}
+Performs the @emph{Recovering a "Locked" Device} procedure to
+restore the flash specified by @var{bank_id} and its associated
+nonvolatile registers to their factory default values (erased).
+This is the only way to remove flash protection or re-enable
+debugging if that capability has been disabled.
+
+Note that the final "power cycle the chip" step in this procedure
+must be performed by hand, since OpenOCD can't do it.
+@quotation Warning
+if more than one Stellaris chip is connected, the procedure is
+applied to all of them.
+@end quotation
+@end deffn
+
 @deffn {Flash Driver} stm32x
 All members of the STM32 microcontroller family from ST Microelectronics
 include internal flash and use ARM Cortex M3 cores.