8141229: [Parfait] Null pointer dereference in cmsstrcasecmp of cmserr.c

Reviewed-by: prr, serb

src/share/native/sun/java2d/cmm/lcms/cmscgats.c

@@ -2545,9 +2545,11 @@ int LocateSample(cmsIT8* it8, const char* cSample)
     for (i=0; i < t->nSamples; i++) {
 
         fld = GetDataFormat(it8, i);
+        if (fld != NULL) {
         if (cmsstrcasecmp(fld, cSample) == 0)
             return i;
     }
+    }
 
     return -1;