cvsps: fix building manpage

Formula/cvsps.rb

@@ -6,10 +6,13 @@ class Cvsps < Formula
   sha1 '8e0b2c66abd521eef2851da2fa5175f14215e9bf'
 
   depends_on 'asciidoc'
+  depends_on 'docbook'
 
   def install
+    # otherwise asciidoc will fail to find docbook
+    ENV['XML_CATALOG_FILES'] = etc/'xml/catalog'
+
     system "make", "all", "cvsps.1"
-    bin.install "cvsps"
-    man1.install gzip("cvsps.1")
+    system "make", "install", "prefix=#{prefix}"
   end
 end