Update requires for devel package, fixes #1931645.

fltk.spec

@@ -6,7 +6,7 @@
 Summary:	C++ user interface toolkit
 Name:		fltk
 Version:	1.3.5
-Release:	10%{?dist}
+Release:	11%{?dist}
 
 # see COPYING (or http://www.fltk.org/COPYING.php ) for exceptions details
 License:	LGPLv2+ with exceptions	
@@ -31,7 +31,7 @@ BuildRequires: doxygen
 BuildRequires: texlive-latex
 # fltk bug with pdf generation, investigate later
 #BuildRequires: texlive-epstopdf
-BuildRequires: libjpeg-devel
+BuildRequires: pkgconfig(libjpeg)
 BuildRequires: pkgconfig(libpng)
 BuildRequires: pkgconfig(gl) pkgconfig(glu) 
 BuildRequires: pkgconfig(ice)
@@ -39,7 +39,7 @@ BuildRequires: pkgconfig(sm)
 BuildRequires: pkgconfig(xext) pkgconfig(xinerama) pkgconfig(xft) pkgconfig(xt) pkgconfig(x11) 
 BuildRequires: pkgconfig(xcursor)
 BuildRequires: pkgconfig(xproto)
-BuildRequires: zlib-devel
+BuildRequires: pkgconfig(zlib)
 BuildRequires: make
 
 %description
@@ -52,9 +52,13 @@ It provides modern GUI functionality without the bloat, and supports
 Summary: Development files for %{name}
 Requires: %{name}%{?_isa} = %{version}-%{release}
 Requires: libstdc++-devel
+Requires: pkgconfig(fontconfig)
 Requires: pkgconfig(gl) pkgconfig(glu)
 Requires: pkgconfig(ice) pkgconfig(sm)
 Requires: pkgconfig(xft) pkgconfig(xt) pkgconfig(x11)
+Requires: pkgconfig(libjpeg)
+Requires: pkgconfig(libpng)
+Requires: pkgconfig(zlib)
 %description devel
 %{summary}.
 
@@ -147,6 +151,9 @@ desktop-file-validate $RPM_BUILD_ROOT%{_datadir}/applications/fluid.desktop
 
 
 %changelog
+* Mon Feb 22 2021 Richard Shaw <hobbes1069@gmail.com> - 1.3.5-11
+- Update requires for devel package, fixes #1931645.
+
 * Tue Jan 26 2021 Fedora Release Engineering <releng@fedoraproject.org> - 1.3.5-10
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_34_Mass_Rebuild