Revert "krdb: Call xrdb with -nocpp" to fix gitk runtime errors

This commit was preventing gitk from starting with
'unknown color name "BACKGROUND"' errors.

This reverts commit d360e3dcb6.


(cherry picked from commit f0764d87fe)

kcms/krdb/krdb.cpp

@@ -493,11 +493,11 @@ void runRdb( uint flags )
   tmpFile.flush();
 
   KProcess proc;
-  proc << QStringLiteral("xrdb") << QStringLiteral("-nocpp")
-#ifdef NDEBUG
-    << QStringLiteral("-quiet")
+#ifndef NDEBUG
+  proc << QStringLiteral("xrdb") << QStringLiteral("-merge") << tmpFile.fileName();
+#else
+  proc << "xrdb" << "-quiet" << "-merge" << tmpFile.fileName();
 #endif
-    << QStringLiteral("-merge") << tmpFile.fileName();
   proc.execute();
 
   applyGtkStyles(exportColors, 1);