Bug#348380: lintian doesn't match all ways of setting DH_COMPAT in debian/rules

[Adam Heath <doogie@brainfood.com>]

Package: lintian
Version: 1.23.14
Severity: minor

--
    } elsif (/^\s*export\s+DH_COMPAT\s*=\s*(\d+)/) {
        $needversiondepends = $1;
--

That doesn't match:

--
DH_COMPAT = 5
export DH_COMPAT
--

Please fix.