cpupower: do not install files to /etc/default/

Improve the installation procedure for the systemd service unit
'cpupower.service', to be more distro-agnostic. Do not install the
service unit configuration file to /etc/default/ (a directory that
is used by Debian and Debian-derivatives and only rarely by other
distros).

Also, clarify the role of the configuration file in its own comments.

Link: https://lore.kernel.org/linux-pm/[e-mail]/T/#ma8a3fa80acc4036af6c754e8ecabacc55b288ad1

Link: https://lore.kernel.org/r/[e-mail]
Fixes: 9c70b779ad91 ("cpupower: add a systemd service to run cpupower")
Signed-off-by: Francesco Poli (wintermute) <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/power/cpupower/Makefile

···
 	$(INSTALL_PROGRAM) $(OUTPUT)cpupower $(DESTDIR)${bindir}
 	$(INSTALL) -d $(DESTDIR)${bash_completion_dir}
 	$(INSTALL_SCRIPT) cpupower-completion.sh '$(DESTDIR)${bash_completion_dir}/cpupower'
-	$(INSTALL) -d $(DESTDIR)${confdir}default
-	$(INSTALL_DATA) cpupower.default '$(DESTDIR)${confdir}default/cpupower'
+	$(INSTALL) -d $(DESTDIR)${confdir}
+	$(INSTALL_DATA) cpupower-service.conf '$(DESTDIR)${confdir}'
 	$(INSTALL) -d $(DESTDIR)${libexecdir}
 	$(INSTALL_PROGRAM) cpupower.sh '$(DESTDIR)${libexecdir}/cpupower'
 	$(INSTALL) -d $(DESTDIR)${libdir}/systemd/system
···
 	- rm -f $(DESTDIR)${includedir}/cpufreq.h
 	- rm -f $(DESTDIR)${includedir}/cpuidle.h
 	- rm -f $(DESTDIR)${bindir}/utils/cpupower
-	- rm -f $(DESTDIR)${confdir}default/cpupower
+	- rm -f $(DESTDIR)${confdir}cpupower-service.conf
 	- rm -f $(DESTDIR)${libexecdir}/cpupower
 	- rm -f $(DESTDIR)${libdir}/systemd/system/cpupower.service
 	- rm -f $(DESTDIR)${mandir}/man1/cpupower.1

tools/power/cpupower/README

···
 
 $ sudo systemctl daemon-reload
 
-If you want to enable this systemd service, edit
-'${DESTDIR}/etc/default/cpupower' (uncommenting at least one of the options,
-depending on your preferences) and then issue the following command:
+If you want to enable this systemd service, edit '/etc/cpupower-service.conf'
+(uncommenting at least one of the options, depending on your preferences)
+and then issue the following command:
 
 $ sudo systemctl enable --now cpupower.service
 

tools/power/cpupower/cpupower.default tools/power/cpupower/cpupower-service.conf

···
 # Copyright (C) 2012, Sébastien Luttringer
 # Copyright (C) 2024-2025, Francesco Poli <[e-mail]>
 
-# Default file for linux-cpupower
+# Configuration file for cpupower.service systemd service unit
+#
+# Edit this file (uncommenting at least one of the options, depending on
+# your preferences) and then enable cpupower.service, if you want cpupower
+# to run at boot with these settings.
 
 # --- CPU clock frequency ---
 
···
 #MIN_FREQ="2.25GHz"
 #MAX_FREQ="3GHz"
 
-# Specific frequency to be set.
+# Set a specific frequency
 # Requires userspace governor to be available.
 # If this option is set, all the previous frequency options are ignored
 #FREQ=
 
 # --- CPU policy ---
 
-# Sets a register on supported Intel processore which allows software to convey
+# Set a register on supported Intel processore which allows software to convey
 # its policy for the relative importance of performance versus energy savings to
 # the processor. See man CPUPOWER-SET(1) for additional details
 #PERF_BIAS=

tools/power/cpupower/cpupower.service.in

···
 # SPDX-License-Identifier: GPL-2.0-or-later
 # Copyright (C) 2012-2020, Sébastien Luttringer
-# Copyright (C) 2024, Francesco Poli <[e-mail]>
+# Copyright (C) 2024-2025, Francesco Poli <[e-mail]>
 
 [Unit]
 Description=Apply cpupower configuration
···
 
 [Service]
 Type=oneshot
-EnvironmentFile=-___CDIR___default/cpupower
+EnvironmentFile=-___CDIR___cpupower-service.conf
 ExecStart=___LDIR___/cpupower
 RemainAfterExit=yes