Remove BuildRoot definition

None of currently supported distributions need that.
It was needed last for EL5 which is EOL now

Signed-off-by: Igor Gnatenko <ignatenkobrain@fedoraproject.org>

neon.spec

@@ -7,7 +7,6 @@ Group: System Environment/Libraries
 URL: http://www.webdav.org/neon/
 Source0: http://www.webdav.org/neon/neon-%{version}.tar.gz
 Patch0: neon-0.27.0-multilib.patch
-BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 BuildRequires: expat-devel, openssl-devel, zlib-devel, krb5-devel, libproxy-devel
 BuildRequires: pkgconfig, pakchois-devel
 Requires: ca-certificates