libgomp.texi: Add more to-be-implemented OpenMP 5.2 features

libgomp/
	* libgomp.texi (Other new OpenMP 5.1 features): Add
	'begin declare target'.
	(Other new OpenMP 5.2 features): New.

diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi
index 56724687fb4..7434643dd1d 100644
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
@@ -343,6 +343,7 @@ The OpenMP 4.5 specification is fully supported.
 @item Support of structured block sequences in C/C++ @tab Y @tab
 @item @code{unconstrained} and @code{reproducible} modifiers on @code{order}
       clause @tab Y @tab
+@item Support @code{begin/end declare target} syntax in C/C++ @tab N @tab
 @end multitable
 
 
@@ -395,6 +396,23 @@ The OpenMP 4.5 specification is fully supported.
 @item @code{omp_cur_iteration} keyword @tab N @tab
 @end multitable
 
+@unnumberedsubsec Other new OpenMP 5.2 features
+
+@multitable @columnfractions .60 .10 .25
+@headitem Description @tab Status @tab Comments
+@item For Fortran, optional comma between directive and clause @tab N @tab
+@item Conforming device numbers and @code{omp_initial_device} and
+      @code{omp_invalid_device} enum/PARAMETER @tab N @tab
+@item Initial value of @emph{default-device-var} ICV with
+      @code{OMP_TARGET_OFFLOAD=mandatory} @tab N @tab
+@item @emph{interop_types} in any position of the modifier list for the @code{init} clause
+      of the @code{interop} construct @tab N @tab
+@item Deprecate specifying multiple modifiers in the @code{map} clause without
+      comma separator @tab N @tab
+@item Deprecate @code{destroy} clause on the @code{depobj} construct with no
+      argument @tab N @tab
+@end multitable
+
 
 @c ---------------------------------------------------------------------
 @c OpenMP Runtime Library Routines