checkinstall: Fix RPM builds

https://bugzilla.novell.com/show_bug.cgi?id=561317

pkgs/tools/package-management/checkinstall/default.nix

@@ -32,6 +32,9 @@ stdenv.mkDerivation {
 
     # Fix a `conflicting types for 'readlink'' error since Glibc 2.19
     ./readlink-types.patch
+
+    # Fix BuildRoot handling in RPM builds.
+    ./set-buildroot.patch
   ]
 
   ++ stdenv.lib.optional (stdenv.system == "x86_64-linux") 

pkgs/tools/package-management/checkinstall/set-buildroot.patch

@@ -0,0 +1,15 @@
+https://build.opensuse.org/package/view_file/openSUSE:13.1/checkinstall/checkinstall-set_buildroot.patch
+
+Index: checkinstall
+===================================================================
+--- a/checkinstall	2009-12-26 20:17:24.000000000 +0100
++++ b/checkinstall	2011-01-31 18:17:56.171593541 +0100
+@@ -2463,7 +2463,7 @@ cd "$DIRECTORIO_FUENTE"
+ 
+ echo
+ echogn "Building RPM package..."
+-$RPMBUILD -bb ${RPM_TARGET_FLAG}${ARCHITECTURE} "$SPEC_PATH" &> ${TMP_DIR}/rpmbuild.log
++$RPMBUILD --buildroot ${BUILDROOT} -bb ${RPM_TARGET_FLAG}${ARCHITECTURE} "$SPEC_PATH" &> ${TMP_DIR}/rpmbuild.log
+ okfail
+ 
+ if [ $? -gt 0 ]; then