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>

perl-Digest-Perl-MD5.spec

@@ -7,7 +7,6 @@ License:	GPL+ or Artistic
 URL:		http://search.cpan.org/dist/Digest-Perl-MD5/
 Source0:	http://search.cpan.org/CPAN/authors/id/D/DE/DELTA/Digest-Perl-MD5-%{version}.tar.gz
 BuildArch:	noarch
-BuildRoot:	%{_tmppath}/%{name}-%{version}-%{release}-root-%(id -nu)
 BuildRequires:	perl-interpreter
 BuildRequires:	perl-generators
 BuildRequires:	perl(Exporter)