docs: Capture additional commands restricted by lockdown

Update documentation to capture that all memrw commands, the minicmd
dump command, and raw memory dumping via hexdump are restricted when
lockdown is enabled. This aligns to recent GRUB code updates.

Signed-off-by: Andrew Hamilton <[email protected]>
Reviewed-by: Daniel Kiper <[email protected]>

Author: hiowaguy

docs/grub.texi

@@ -5124,6 +5124,8 @@ This module provides support for commands @command{read_byte},
 write data to physical memory (addresses). The "read" commands accept one
 parameter to specify the source address. The "write" commands require either two
 or three parameters, with the order: address, value, <optional mask>.
+Note: The commands provided by this module are not allowed when lockdown is
+enforced (@pxref{Lockdown}).
 
 @node memtools_module
 @section memtools
@@ -5137,6 +5139,8 @@ including: @command{cat}, @command{help}, @command{dump}, @command{rmmod},
 @command{lsmod}, and @command{exit}. The version of the commands in this module
 are similar to their full-fledged counterparts implemented in other GRUB
 modules.
+Note: The @command{dump} command is not allowed when lockdown is enforced
+(@pxref{Lockdown}).
 
 @node minix_module
 @section minix
@@ -7196,6 +7200,11 @@ to be shown.
 
 If given the special device named @samp{(mem)}, then the @samp{offset} given to
 @option{--skip} is treated as the address of a memory location to dump from.
+
+Note: The dumping of RAM memory (by the (mem) argument) is not allowed when
+when lockdown is enforced (@pxref{Lockdown}). The dumping of disk or file
+data is allowed when lockdown is enforced.
+
 @end deffn