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>

scripts/kconfig/.gitignore

 # SPDX-License-Identifier: GPL-2.0-only
 /conf
 /[gmnq]conf
+/[gmnq]conf-bin
 /[gmnq]conf-cflags
 /[gmnq]conf-libs
-/qconf-bin
 /qconf-moc.cc

scripts/kconfig/Makefile

@@ -209,7 +209,7 @@ $(obj)/gconf: | $(obj)/gconf-libs
 $(obj)/gconf.o: | $(obj)/gconf-cflags
 
 # check if necessary packages are available, and configure build flags
-cmd_conf_cfg = $< $(addprefix $(obj)/$*conf-, cflags libs bin)
+cmd_conf_cfg = $< $(addprefix $(obj)/$*conf-, cflags libs bin); touch $(obj)/$*conf-bin
 
 $(obj)/%conf-cflags $(obj)/%conf-libs $(obj)/%conf-bin: $(src)/%conf-cfg.sh
 	$(call cmd,conf_cfg)