ngrep: add license information

[Peter: use BSD-4c-like for license]
Signed-off-by: Phil Eichinger <phil@zankapfel.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/ngrep/ngrep.mk

@@ -7,6 +7,8 @@
 NGREP_VERSION = 1.45
 NGREP_SOURCE = ngrep-$(NGREP_VERSION).tar.bz2
 NGREP_SITE = http://downloads.sourceforge.net/project/ngrep/ngrep/$(NGREP_VERSION)
+NGREP_LICENSE = BSD-4c-like
+NGREP_LICENSE_FILES = LICENSE.txt
 NGREP_INSTALL_STAGING = YES
 NGREP_CONF_ENV = LDFLAGS="-lpcre"
 NGREP_CONF_OPT =  \