[source] busybox: don't install NTP scripts if NTP isn't configured

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/0b24850e97789818fadcbce4b8de4abc429fd9f2

commit 0b24850e97789818fadcbce4b8de4abc429fd9f2
Author: Philip Prindeville <philipp at redfish-solutions.com>
AuthorDate: Mon Feb 6 15:26:49 2017 -0700

    busybox: don't install NTP scripts if NTP isn't configured
    
    If you're using Chrony or NTPD you don't want the busybox NTP server
    as well.  Make it's installation truly conditional.
    
    Signed-off-by: Philip Prindeville <philipp at redfish-solutions.com>
    Signed-off-by: Felix Fietkau <nbd at nbd.name> [simplify]
---
 package/utils/busybox/Makefile | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/package/utils/busybox/Makefile b/package/utils/busybox/Makefile
index b75b455..48d9457 100644
--- a/package/utils/busybox/Makefile
+++ b/package/utils/busybox/Makefile
@@ -112,9 +112,13 @@ endef
 define Package/busybox/install
 	$(INSTALL_DIR) $(1)/etc/init.d
 	$(CP) $(PKG_INSTALL_DIR)/* $(1)/
+ifneq ($(CONFIG_BUSYBOX_CONFIG_CROND),)
 	$(INSTALL_BIN) ./files/cron $(1)/etc/init.d/cron
+endif
+ifneq ($(CONFIG_BUSYBOX_CONFIG_NTPD),)
 	$(INSTALL_BIN) ./files/sysntpd $(1)/etc/init.d/sysntpd
 	$(INSTALL_BIN) ./files/ntpd-hotplug $(1)/usr/sbin/ntpd-hotplug
+endif
 	-rm -rf $(1)/lib64
 endef