Use defined/undefined macro for improved readability

keepassxc.spec

@@ -32,7 +32,7 @@ Patch0:         xcb.patch
 BuildRequires:  botan2-devel
 BuildRequires:  cmake >= 3.1
 BuildRequires:  desktop-file-utils
-%if 0%{?el8}
+%if %{defined el8}
 BuildRequires:  gcc-toolset-11-gcc-c++
 BuildRequires:  gcc-toolset-11-annobin-plugin-gcc
 %else
@@ -48,7 +48,7 @@ BuildRequires:  libusb1-devel
 BuildRequires:  libXi-devel
 BuildRequires:  libXtst-devel
 BuildRequires:  libyubikey-devel
-%if 0%{?el8}
+%if %{defined el8}
 BuildRequires:  minizip1.2-devel
 %else
 BuildRequires:  minizip-devel
@@ -67,7 +67,7 @@ BuildRequires:  zlib-devel
 # For EL8 missing rubygem-asciidoctor read
 # https://bugzilla.redhat.com/show_bug.cgi?id=1859390
 # https://bugzilla.redhat.com/show_bug.cgi?id=1820896
-%if ! 0%{?el8}
+%if %{undefined el8}
 BuildRequires:  rubygem-asciidoctor
 %endif
 
@@ -110,7 +110,7 @@ information can be considered as quite safe.
 # beyond the undefined symbols.  It really shold be investigated further.
 # Disable LTO
 %define _lto_cflags %{nil}
-%if 0%{?el8}
+%if %{defined el8}
 . /opt/rh/gcc-toolset-11/enable
 %endif
 # -DWITH_XC_DOCS=OFF is needed on EL due missing rubygem-asciidoctor
@@ -173,7 +173,7 @@ appstream-util validate-relax --nonet %{buildroot}%{_datadir}/metainfo/org.%{nam
 %{_libdir}/%{name}
 # Missing rubygem-asciidoctor in EL8 does not allow having documentation in EL8
 # Read https://bugzilla.redhat.com/show_bug.cgi?id=1859390
-%if ! 0%{?el8}
+%if %{undefined el8}
 %{_mandir}/man1/%{name}-cli.1*
 %{_mandir}/man1/%{name}.1*
 %endif