Fix crash in some pdf

Has to be 3 and not nComps since it's a output buffer, a the input one
Bug 34357
diff --git a/poppler/GfxState.cc b/poppler/GfxState.cc
index 78ac5a8..2ce11fb 100644
--- a/poppler/GfxState.cc
+++ b/poppler/GfxState.cc
@@ -1599,7 +1599,7 @@
 				       int length) {
 #ifdef USE_CMS
   if (lineTransform != 0) {
-    Guchar* tmp = (Guchar *)gmallocn(nComps * length, sizeof(Guchar));
+    Guchar* tmp = (Guchar *)gmallocn(3 * length, sizeof(Guchar));
     lineTransform->doTransform(in, tmp, length);
     for (int i = 0; i < length; ++i) {
         Guchar *current = tmp + (i * 3);