package/wireshark: add libcap optional dependency

libcap is an optional dependency which is enabled by default since at
least version 1.8.0 and
https://github.com/wireshark/wireshark/commit/9250a69a9976617c735679aa5383e53802e5b43e

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit f70149c80cda5d2f6bbe2266b247d52818391cda)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/wireshark/wireshark.mk

@@ -65,6 +65,13 @@ else
 WIRESHARK_CONF_OPTS += -DENABLE_GNUTLS=OFF
 endif
 
+ifeq ($(BR2_PACKAGE_LIBCAP),y)
+WIRESHARK_CONF_OPTS += -DENABLE_CAP=ON
+WIRESHARK_DEPENDENCIES += libcap
+else
+WIRESHARK_CONF_OPTS += -DENABLE_CAP=OFF
+endif
+
 ifeq ($(BR2_PACKAGE_LIBKRB5),y)
 WIRESHARK_CONF_OPTS += -DENABLE_KERBEROS=ON
 WIRESHARK_DEPENDENCIES += libkrb5