Kapt: Allow to make CompilerConfiguration mutable again

(cherry picked from commit 0780de8)

compiler/frontend/src/org/jetbrains/kotlin/config/CompilerConfiguration.java

@@ -96,11 +96,10 @@ public class CompilerConfiguration {
 
     public void setReadOnly(boolean readOnly) {
         if (readOnly != this.readOnly) {
-            checkReadOnly();
             this.readOnly = readOnly;
         }
     }
-    
+
     public boolean isReadOnly() {
         return readOnly;
     }