use %%samples feature macro

... instead of sprinkling %%rhel version checks all over

LibRaw.spec

@@ -1,3 +1,9 @@
+
+# feature macro to enable samples (or not)
+%if 0%{?rhel} != 7
+%global samples 1
+%endif
+
 Summary: Library for reading RAW files obtained from digital photo cameras
 Name: LibRaw
 Version: 0.19.5
@@ -39,14 +45,12 @@ Requires: %{name}-devel%{?_isa} = %{version}-%{release}
 %description static
 LibRaw static development libraries.
 
-%if 0%{?rhel} != 7
 %package samples
 Summary: LibRaw sample programs
 Requires: %{name} = %{version}-%{release}
 
 %description samples
 LibRaw sample programs
-%endif
 
 %prep
 %setup -q
@@ -56,11 +60,7 @@ LibRaw sample programs
 %build
 autoreconf -if
 %configure \
-%if 0%{?rhel} == 7
-    --enable-examples=no \
-%else
-    --enable-examples=yes \
-%endif
+    --enable-examples=%{?samples:yes}%{!?samples:no} \
     --enable-jasper \
     --enable-jpeg \
     --enable-lcms \
@@ -100,7 +100,9 @@ rm -fv %{buildroot}%{_libdir}/lib*.la
 
 %files devel
 %doc manual
+#if 0%{?samples}
 %doc samples
+#endif
 %{_includedir}/libraw/
 %{_libdir}/libraw.so
 %{_libdir}/libraw_r.so
@@ -108,7 +110,7 @@ rm -fv %{buildroot}%{_libdir}/lib*.la
 %{_libdir}/pkgconfig/libraw_r.pc
 %exclude %{_docdir}/libraw/*
 
-%if 0%{?rhel} != 7
+%if 0%{?samples}
 %files samples
 %{_bindir}/*
 %endif