Use pkgconfig for BuildRequires

https://fedoraproject.org/wiki/Packaging:PkgConfigBuildRequires

orca.spec

@@ -11,16 +11,17 @@ Source0:        https://download.gnome.org/sources/%{name}/3.17/%{name}-%{versio
 
 BuildArch:      noarch
 
+BuildRequires:  pkgconfig(atk-bridge-2.0)
+BuildRequires:  pkgconfig(atspi-2)
+BuildRequires:  pkgconfig(liblouis)
+BuildRequires:  pkgconfig(pygobject-3.0)
 BuildRequires:  brlapi-devel
 BuildRequires:  brltty
 BuildRequires:  gettext
 BuildRequires:  intltool
-BuildRequires:  at-spi2-core-devel
-BuildRequires:  liblouis-devel
 BuildRequires:  liblouis-python3
 BuildRequires:  gtk3-devel
 BuildRequires:  itstool
-BuildRequires:  pygobject3-devel
 BuildRequires:  python3-brlapi
 BuildRequires:  python3-devel
 BuildRequires:  python3-pyatspi
@@ -84,6 +85,7 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 - Update to 3.17.4
 - Update URL
 - Update man page glob in files section
+- Use pkgconfig for BuildRequires
 
 * Tue Jun 30 2015 Kalev Lember <klember@redhat.com> - 3.17.3-1
 - Update to 3.17.3