DO NOT MERGE Change an bionic test case name.

The original test case name __pthread_clone was changed to __bionic_clone in the following CL, but it's not updated in CTS. See https://android-review.googlesource.com/#/c/70142/. Below is its brief:

commit 70b24b1cc2a1a4436b1fea3f8b76616fdcb27224
Author: Elliott Hughes <enh@google.com>
Date:   Fri Nov 15 11:51:07 2013 -0800

    Switch pthread_create over to __bionic_clone.
    
    Bug: 8206355
    Bug: 11693195
    Change-Id: I04aadbc36c87e1b7e33324b9a930a1e441fbfed6


Bug: 15385970
Change-Id: I2d203658feb493ff25d9d1d4d3bd66a683215487