wireshark +qt fails to build

[AlD (Daniel Albers)]

Trying to install wireshark @1.12.8 +qt fails during configure as pkg-config checks the wrong paths:

:info:configure checking for Qt5Core - version >= 4.6.0... no
:info:configure checking for QtCore - version >= 4.6.0... no
:info:configure configure: error: Qt is not available
:info:configure Command failed:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_wireshark/wireshark/work/wireshark-1.12.8" && ./configure --prefix=/opt/local --disable-osx-deploy-target --disable-usr-local --without-adns --with-c-ares=/opt/local --without-lua --with-pcap=/opt/local --with-ssl=/opt/local --with-zlib=/opt/local --mandir=\${prefix}/share/man --infodir=\${prefix}/share/info --disable-warnings-as-errors --with-krb5=/opt/local --with-gnutls=yes --with-libgcrypt-prefix=/opt/local --enable-ipv6 --with-libsmi=/opt/local --with-geoip=/opt/local --with-qt=yes --with-gtk2=no --with-gtk3=no --with-portaudio=/opt/local
:info:configure Exit code: 1

$ grep '[^$]PKG_CONFIG' /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_wireshark/wireshark/work/wireshark-1.12.8/config.log
ac_cv_env_PKG_CONFIG_LIBDIR_set=
ac_cv_env_PKG_CONFIG_LIBDIR_value=
ac_cv_env_PKG_CONFIG_PATH_set=
ac_cv_env_PKG_CONFIG_PATH_value=
ac_cv_env_PKG_CONFIG_set=
ac_cv_env_PKG_CONFIG_value=
ac_cv_path_PKG_CONFIG=/opt/local/bin/pkg-config
ac_cv_path_ac_pt_PKG_CONFIG=/opt/local/bin/pkg-config