Bug#712045: ghostscript-cups: colord icc profile empty

[Alexey Galakhov <agalakhov@yandex-team.ru>]

Applying of the previous patch resulted in regression. Sometimes colord
returns empty ICC filename which results in ghostscript failure. In this
case no ICC option could be used.

The attached patch fixes this.

--- ghostscript-9.05~dfsg.orig/cups/gstoraster.c	2013-06-12 19:48:26.000000000 +0600
+++ ghostscript-9.05~dfsg/cups/gstoraster.c	2013-06-18 19:07:47.000000000 +0600
@@ -657,7 +657,7 @@
   cupsArrayAdd(gs_args, strdup(tmpstr));
 
   /* set the device output ICC profile */
-  if(icc_profile != NULL) {
+  if(icc_profile != NULL && icc_profile[0] != '\0') {
     snprintf(tmpstr, sizeof(tmpstr), "-sOutputICCProfile=%s", icc_profile);
     cupsArrayAdd(gs_args, strdup(tmpstr));
   }