Rework build conditionals for firebird+kf5+kf6 and fix supplements for kf5

This makes the build features a bit more manageable and prepares
LibreOffice a little bit for EPEL 10.

libreoffice.spec

@@ -46,6 +46,30 @@
 %bcond_with serverconfig
 %endif
 
+# Disable firebird for RHEL
+%if 0%{?rhel}
+%bcond_with firebird
+%else
+%bcond_without firebird
+%endif
+
+# Handle KDE/Qt integration for Fedora and RHEL/EPEL
+%if 0%{?rhel} && 0%{?rhel} < 10
+%bcond_with kf5
+%bcond_with kf6
+%endif
+
+# KDE Plasma 5 integration only for Fedora
+%if 0%{?fedora}
+%bcond_without kf5
+%endif
+
+# KDE Plasma 6 integration for Fedora and RHEL/EPEL 10+
+%if 0%{?fedora} || 0%{?rhel} >= 10
+%bcond_without kf6
+%endif
+
+
 # generated by %%langpack definitions
 %global langpack_langs %{nil}
 
@@ -148,7 +172,7 @@ BuildRequires: boost-devel
 BuildRequires: cups-devel
 BuildRequires: dragonbox-static
 BuildRequires: fontpackages-devel
-%if 0%{?fedora}
+%if %{with firebird}
 BuildRequires: firebird-devel
 %endif
 BuildRequires: glm-devel
@@ -217,8 +241,11 @@ BuildRequires: %{libo_python_executable}
 #BuildRequires: gdb
 
 # libs / headers - conditional
-%if 0%{?fedora}
+%if 0%{?fedora} || 0%{?rhel} >= 10
 BuildRequires: pkgconfig(libe-book-0.1)
+%endif
+
+%if %{with kf5}
 BuildRequires: qt5-qtbase-devel
 BuildRequires: qt5-qtx11extras-devel
 BuildRequires: kf5-kconfig-devel
@@ -227,7 +254,9 @@ BuildRequires: kf5-kdelibs4support-devel
 BuildRequires: kf5-ki18n-devel
 BuildRequires: kf5-kio-devel
 BuildRequires: kf5-kwindowsystem-devel
+%endif
 
+%if %{with kf6}
 BuildRequires: qt6-qtbase-devel
 BuildRequires: kf6-kconfig-devel
 BuildRequires: kf6-kcoreaddons-devel
@@ -385,7 +414,7 @@ to be written in python.
 
 %package base
 Summary: Database front-end for LibreOffice
-%if 0%{?fedora}
+%if %{with firebird}
 Requires: firebird
 %endif
 %ifarch %{java_arches}
@@ -668,7 +697,7 @@ Supplements: (%{name}-core%{?_isa} and gtk4%{?_isa})
 %description gtk4
 An experimental plug-in for LibreOffice that enables integration into GTK+ 4 environment.
 
-%if 0%{?fedora}
+%if %{with kf5}
 
 %package kf5
 Summary: LibreOffice KDE Frameworks 5 integration plug-in
@@ -680,11 +709,17 @@ Obsoletes: libreoffice-kde4 < 1:6.3.0.0
 Obsoletes: libreoffice-kde5 < 1:6.4.7.3
 Obsoletes: libreoffice-kde4-debuginfo < 1:6.3.0.0
 Obsoletes: libreoffice-kde5-debuginfo < 1:6.4.7.3
+%if (0%{?fedora} && 0%{?fedora} < 40)
 Supplements: (%{name}-core%{?_isa} and plasma-workspace)
+%endif
 
 %description kf5
 A plug-in for LibreOffice that enables integration into the KDE Frameworks 5.
 
+%endif
+
+%if %{with kf6}
+
 %package kf6
 Summary: LibreOffice KDE Frameworks 6 integration plug-in
 Requires: %{name}-core%{?_isa} = %{epoch}:%{version}-%{release}
@@ -1110,12 +1145,8 @@ export ARCH_FLAGS
 export CFLAGS="$ARCH_FLAGS -I%{_includedir}/zxcvbn -I%{_includedir}/KF6/KConfig/"
 export CXXFLAGS="$ARCH_FLAGS -I%{_includedir}/zxcvbn -I%{_includedir}/KF6/KConfig/"
 
-%if 0%{?rhel}
-%define distrooptions --disable-eot --disable-firebird-sdbc
-%else
-# fedora
-%define distrooptions --enable-eot --enable-kf5 --enable-kf6
-%endif
+# Distro build options
+%define distrooptions --enable-eot %{!?with_firebird:--disable-firebird-sdbc} %{?with_kf5:--enable-kf5} %{?with_kf6:--enable-kf6}
 
 %ifarch %{java_arches}
 %define javaoptions --with-java --enable-ext-nlpsolver --enable-ext-wiki-publisher
@@ -1900,7 +1931,7 @@ rm -f %{buildroot}%{baseinstdir}/program/classes/smoketest.jar
 %endif
 %{baseinstdir}/program/libabplo.so
 %{baseinstdir}/program/libdbplo.so
-%if 0%{?fedora}
+%if %{with firebird}
 %{baseinstdir}/program/libfirebird_sdbclo.so
 %endif
 %ifarch %{java_arches}
@@ -2276,14 +2307,17 @@ gtk-update-icon-cache -q %{_datadir}/icons/hicolor &>/dev/null || :
 %endif
 %{baseinstdir}/program/libvclplug_gtk4lo.so
 
-%if 0%{?fedora}
-
+%if %{with kf5}
 %files kf5
 %{baseinstdir}/program/kf5.abignore
 %{baseinstdir}/program/libkf5be1lo.so
 %{baseinstdir}/program/libvclplug_kf5lo.so
 %{baseinstdir}/program/libvclplug_qt5lo.so
 
+%endif
+
+%if %{with kf6}
+
 %files kf6
 %{baseinstdir}/program/libvclplug_kf6lo.so
 %{baseinstdir}/program/libvclplug_qt6lo.so