[PATCH] [doc] Fix memory tagging section type

[Luis Machado via Gdb-patches <gdb-patches@sourceware.org>]

It was reported to me that on Ubuntu 14.04 (fairly old) the documentation
fails to build with the following:

gdb/doc/gdb.texinfo:10888: warning: node `Memory' is up for `Memory Tagging' in sectioning but not in menu
gdb/doc/gdb.texinfo:10693: node `Memory' lacks menu item for `Memory Tagging' despite being its Up target
Makefile:491: recipe for target 'gdb.info' failed
make[3]: *** [gdb.info] Error 1

This doesn't seem to happen on Ubuntu 18.04/20.04, but it does make sense.

Fix this by turning @subsection into a @section and adding the
"Memory Tagging" entry to the menu.

gdb/doc/ChangeLog:

YYYY-MM-DD  Luis Machado  <luis.machado@linaro.org>

	* gdb.textinfo (Memory Tagging): Make it a @section and add to the
	menu.
---
 gdb/doc/gdb.texinfo | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index dbf878cdbc3..7dbffb65d53 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -10118,6 +10118,7 @@ being passed the type of @var{arg} as the argument.
 * Arrays::                      Artificial arrays
 * Output Formats::              Output formats
 * Memory::                      Examining memory
+* Memory Tagging::              Memory Tagging
 * Auto Display::                Automatic display
 * Print Settings::              Print settings
 * Pretty Printing::             Python pretty printing
@@ -10886,7 +10887,7 @@ target supports computing the CRC checksum of a block of memory
 @end table
 
 @node Memory Tagging
-@subsection Memory Tagging
+@section Memory Tagging
 
 Memory tagging is a memory protection technology that uses a pair of tags to
 validate memory accesses through pointers.  The tags are integer values
-- 
2.25.1