gnu-config: Update to 20250709

gnu-config: Update to 20250709

The version 20250709 is the author date.

* The changes are:
a2287c3 Adjust 'time-stamp' variables to modern Emacs
973e3e6 config.sub: Add Tock OS support
3a71dc1 config.sub: recognize banan_os
f91a544 config.sub: fix a duplicated case pattern
484648c config.sub: Include support for arm64_32 and iOS/tvOS/watchOS simulators
84cc2cc Update copyright years
7f41495 config.sub: add intelgt as a basic machine
9f6e0fe ironclad: change ironclad to ironclad-mlibc

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>