Vararg in constructor isn't loaded correctly from bytecode

#KT-3251 Fixed

compiler/testData/loadKotlin/constructor/ConstructorVararg.kt

@@ -0,0 +1,3 @@
+package test
+
+class A(vararg a: Int) {}

compiler/testData/loadKotlin/constructor/ConstructorVararg.txt

@@ -0,0 +1,5 @@
+package test
+
+internal final class A {
+    /*primary*/ public constructor A(/*0*/ vararg a : jet.Int /*jet.IntArray*/)
+}