Perl: extra "return" removed.

src/http/modules/perl/nginx.xs

diff --git a/src/http/modules/perl/nginx.xs b/src/http/modules/perl/nginx.xs
index bbfef07..de67d51 100644
--- a/src/http/modules/perl/nginx.xs
+++ b/src/http/modules/perl/nginx.xs
@@ -419,7 +419,7 @@
 
     p = ngx_pnalloc(r->pool, len);
     if (p == NULL) {
-        return XSRETURN_UNDEF;
+        XSRETURN_UNDEF;
     }
 
     data = p;