sylpheed: add license info

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/sylpheed/sylpheed.mk

@@ -8,6 +8,8 @@ SYLPHEED_VERSION_MINOR = 0
 SYLPHEED_VERSION = $(SYLPHEED_VERSION_MAJOR).$(SYLPHEED_VERSION_MINOR)
 SYLPHEED_SOURCE = sylpheed-$(SYLPHEED_VERSION).tar.bz2
 SYLPHEED_SITE = http://sylpheed.sraoss.jp/sylpheed/v$(SYLPHEED_VERSION_MAJOR)
+SYLPHEED_LICENSE = GPLv2+ (executables), LGPLv2.1+ (library, attachment plugin)
+SYLPHEED_LICENSE_FILES = COPIYNG COPYING.LIB
 
 SYLPHEED_CONF_OPT = --disable-gtkspell