boost: force build of meta-package to satisfy other package dependencies

Signed-off-by: Ted Hess <thess@kitschensync.net>

libs/boost/Makefile

 
 PKG_NAME:=boost
 PKG_VERSION:=1_58_0
-PKG_RELEASE:=4
+PKG_RELEASE:=5
 
 PKG_SOURCE:=$(PKG_NAME)_$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=@SF/boost
   true
 endef
 
+define Package/boost/install
+  true
+endef
+
 define Package/boost
   $(call Package/boost/Default)
   TITLE+= packages