[lworld][c1] SharedRuntime::fixup_callers_callsite is wrong when caller is C1

The following new test fails when added to http://hg.openjdk.java.net/valhalla/valhalla/file/e1b581738b26/test/hotspot/jtreg/compiler/valhalla/valuetypes/TestCallingConventionC1.java

    // C1->C1 - caller is compiled first. It invokes callee(test97) a few times while the
    // callee is executed by the interpreter. Then, callee is compiled
    // and SharedRuntime::fixup_callers_callsite is called to fix up the
    // callsite from test97_verifier->test97.
    @Test(compLevel = C1)
    public int test97(Point p1, Point p2) {
        return test97_helper(p1, p2);
    }

    @DontInline @DontCompile
    public int test97_helper(Point p1, Point p2) {
        return p1.x + p1.y + p2.x + p2.y;
    }

    @ForceCompile(compLevel = C1)
    public void test97_verifier(boolean warmup) {
        int count = warmup ? 1 : 20;
        for (int i=0; i<count; i++) {
            int result = test97(pointField1, pointField2);
            int n = test97_helper(pointField1, pointField2);
            Asserts.assertEQ(result, n);
        }
    }