which: add license info

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/which/which.mk

@@ -6,5 +6,7 @@
 
 WHICH_VERSION = 2.20
 WHICH_SITE = http://carlo17.home.xs4all.nl/which
+WHICH_LICENSE = GPLv3+
+WHICH_LICENSE_FILES = COPYING
 
 $(eval $(autotools-package))