kconfig: Update all declared targets

kconfig: Update all declared targets

Currently qconf-cfg.sh is the only script that touches the "-bin"
target, even though all of the conf_cfg rules declare that they do.
Make the recipe unconditionally touch all declared targets to avoid
incompatibilities with upcoming versions of GNU make:
https://lists.gnu.org/archive/html/info-gnu/2022-10/msg00008.html

e.g.
scripts/kconfig/Makefile:215: warning: pattern recipe did not update peer target 'scripts/kconfig/nconf-bin'.
scripts/kconfig/Makefile:215: warning: pattern recipe did not update peer target 'scripts/kconfig/mconf-bin'.
scripts/kconfig/Makefile:215: warning: pattern recipe did not update peer target 'scripts/kconfig/gconf-bin'.

Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>