doc: release: 4.3: deprecate CONFIG_XOPEN_STREAMS (again)

Deprecate the CONFIG_XOPEN_STREAMS Kconfig option in favour of
CONFIG_XSI_STREAMS, which matches the naming conventions of other XSI
Kconfig options and the actual Option Group name in the specification.

Please use CONFIG_XSI_STREAMS instead.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>

Author: cfriedt

doc/releases/release-notes-4.3.rst

@@ -95,6 +95,8 @@ Deprecated APIs and options
 
 * RISCV's :kconfig:option:`CONFIG_EXTRA_EXCEPTION_INFO` is deprecated. Use :kconfig:option:`CONFIG_EXCEPTION_DEBUG` instead.
 
+* :kconfig:option:`CONFIG_XOPEN_STREAMS` was deprecated. Instead, use :kconfig:option:`CONFIG_XSI_STREAMS`.
+
 New APIs and options
 ====================