libgomp.texi: Status 'P' for 'assume', remove duplicated line

	* libgomp.texi (OpenMP 5.1): Mark 'assume' as implemented
	for C/C++. Remove duplicated 'begin declare target' entry.
diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi
index 5aef987..2b11f30 100644
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
@@ -287,7 +287,7 @@
       @code{append_args} @tab N @tab
 @item @code{dispatch} construct @tab N @tab
 @item device-specific ICV settings with environment variables @tab Y @tab
-@item @code{assume} directive @tab N @tab
+@item @code{assume} directive @tab P @tab Only C/C++
 @item @code{nothing} directive @tab Y @tab
 @item @code{error} directive @tab Y @tab
 @item @code{masked} construct @tab Y @tab
@@ -348,7 +348,6 @@
 @item Support @code{begin/end declare target} syntax in C/C++ @tab N @tab
 @item Pointer predetermined firstprivate getting initialized
 to address of matching mapped list item per 5.1, Sect. @tab N @tab
-@item @code{begin declare target} directive @tab N @tab
 @item For Fortran, diagnose placing declarative before/between @code{USE},
       @code{IMPORT}, and @code{IMPLICIT} as invalid @tab N @tab
 @end multitable