flock: enable alternatives support

Fixes FS#1510

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

package/utils/busybox/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=busybox
 PKG_VERSION:=1.28.3
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 PKG_FLAGS:=essential
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2
@@ -47,6 +47,7 @@ define Package/busybox
   DEPENDS:=+BUSYBOX_USE_LIBRPC:librpc +BUSYBOX_CONFIG_PAM:libpam +BUSYBOX_CONFIG_NTPD:jsonfilter
   MENU:=1
   ALTERNATIVES:=\
+    $(call BUSYBOX_IF_ENABLED,FLOCK,	100:/usr/bin/flock:/bin/busybox) \
     $(call BUSYBOX_IF_ENABLED,FREE,	100:/usr/bin/free:/bin/busybox) \
     $(call BUSYBOX_IF_ENABLED,IP,	100:/sbin/ip:/bin/busybox) \
     $(call BUSYBOX_IF_ENABLED,KILL,	100:/bin/kill:/bin/busybox) \

package/utils/util-linux/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=util-linux
 PKG_VERSION:=2.32
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=@KERNEL/linux/utils/$(PKG_NAME)/v2.32
@@ -198,6 +198,7 @@ endef
 define Package/flock
 $(call Package/util-linux/Default)
   TITLE:=manage locks from shell scripts
+  ALTERNATIVES:=200:/usr/bin/flock:/usr/bin/util-linux-flock
 endef
 
 define Package/flock/description
@@ -591,7 +592,7 @@ endef
 
 define Package/flock/install
 	$(INSTALL_DIR) $(1)/usr/bin
-	$(INSTALL_BIN) $(PKG_INSTALL_DIR)/usr/bin/flock $(1)/usr/bin/
+	$(INSTALL_BIN) $(PKG_INSTALL_DIR)/usr/bin/flock $(1)/usr/bin/util-linux-flock
 endef
 
 define Package/fstrim/install