zeromq: add PGM/EPGM support

This adds support for Pragmatic General Multicast protocol on raw
IP (PGM, RFC 3208) or UDP frames (EPGM) for use as zeromq reliable
multicast transport. The library relies on openpgm package to
implement the protocol itself.

Signed-off-by: Alexander Lukichev <alexander.lukichev@gmail.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/zeromq/Config.in

@@ -23,3 +23,12 @@ config BR2_PACKAGE_ZEROMQ
 	  ØMQ is from iMatix and is LGPL open source.
 
 	  http://www.zeromq.org/
+
+config BR2_PACKAGE_ZEROMQ_PGM
+	bool "PGM/EPGM support"
+	depends on BR2_PACKAGE_ZEROMQ
+	select BR2_PACKAGE_OPENPGM
+	help
+	  Add support for Pragmatic General Multicast protocol (RFC 3208)
+	  implemented either over raw IP packets or UDP datagrams
+	  (encapsulated PGM). This requires OpenPGM library.

package/zeromq/zeromq.mk

@@ -11,4 +11,9 @@ ZEROMQ_DEPENDENCIES = util-linux
 ZEROMQ_LICENSE = LGPLv3+ with exceptions
 ZEROMQ_LICENSE_FILES = COPYING COPYING.LESSER
 
+ifeq ($(BR2_PACKAGE_ZEROMQ_PGM),y)
+	ZEROMQ_DEPENDENCIES += host-pkgconf openpgm
+	ZEROMQ_CONF_OPT = --with-system-pgm
+endif
+
 $(eval $(autotools-package))