[build]: add swss dbg package into deb (#506)

Author: lguohan

rules/swss.mk

@@ -6,3 +6,8 @@ $(SWSS)_DEPENDS += $(LIBSAIREDIS_DEV) $(LIBSAIMETADATA_DEV) $(LIBTEAM_DEV) \
     $(LIBTEAMDCT) $(LIBTEAM_UTILS)
 $(SWSS)_RDEPENDS += $(LIBSAIREDIS) $(LIBSAIMETADATA) $(LIBTEAM)
 SONIC_DPKG_DEBS += $(SWSS)
+
+SWSS_DBG = swss-dbg_1.0.0_amd64.deb
+$(SWSS_DBG)_DEPENDS += $(SWSS)
+$(SWSS_DBG)_RDEPENDS += $(SWSS)
+$(eval $(call add_derived_package,$(SWSS),$(SWSS_DBG)))