libpcap: Bump the minimum required version to >= 1.5.0

libpcap-1.5.0 introduced a function to enforce immediate mode (on all
platforms) which the follow-up patches will rely on.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

libvirt.spec.in

@@ -302,7 +302,7 @@ BuildRequires: yajl-devel
 %if %{with_sanlock}
 BuildRequires: sanlock-devel >= 2.4
 %endif
-BuildRequires: libpcap-devel
+BuildRequires: libpcap-devel >= 1.5.0
 BuildRequires: libnl3-devel
 BuildRequires: libselinux-devel
 BuildRequires: dnsmasq >= 2.41

m4/virt-libpcap.m4

@@ -22,7 +22,7 @@ AC_DEFUN([LIBVIRT_ARG_LIBPCAP], [
 ])
 
 AC_DEFUN([LIBVIRT_CHECK_LIBPCAP], [
-  LIBPCAP_REQUIRED="1.0.0"
+  LIBPCAP_REQUIRED="1.5.0"
   LIBPCAP_CONFIG="pcap-config"
   LIBPCAP_CFLAGS=""
   LIBPCAP_LIBS=""