package/alsa-utils: fix install if directories exist

"mkdir" (without "-p") fails if the target directory exists, which means
that if alsa-utils is being reinstalled or if other files have
previously been installed in the alsa-state.d or alsa-restore.d
directories the installation will fail.

Switch to "$(INSTALL) -d" which allows us to be explicit about the
permissions and handles the case of a pre-existing directory correctly.

Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/alsa-utils/alsa-utils.mk

@@ -86,10 +86,10 @@ define ALSA_UTILS_INSTALL_INIT_SYSTEMD
 		$(TARGET_DIR)/usr/lib/systemd/system/alsa-restore.service
 	$(INSTALL) -D -m 0644 $(@D)/alsactl/alsa-state.service \
 		$(TARGET_DIR)/usr/lib/systemd/system/alsa-state.service
-	mkdir $(TARGET_DIR)/usr/lib/systemd/system/alsa-restore.service.d
+	$(INSTALL) -d -m 0755 $(TARGET_DIR)/usr/lib/systemd/system/alsa-restore.service.d
 	printf '[Install]\nWantedBy=multi-user.target\n' \
 		>$(TARGET_DIR)/usr/lib/systemd/system/alsa-restore.service.d/buildroot-enable.conf
-	mkdir $(TARGET_DIR)/usr/lib/systemd/system/alsa-state.service.d
+	$(INSTALL) -d -m 0755 $(TARGET_DIR)/usr/lib/systemd/system/alsa-state.service.d
 	printf '[Install]\nWantedBy=multi-user.target\n' \
 		>$(TARGET_DIR)/usr/lib/systemd/system/alsa-state.service.d/buildroot-enable.conf;
 endef