TEST: Disable leak checking for mksh; it's way too leaky.

When each shell leaks ~240 allocations, you can't see the leaks from
the program you ran with "adb shell".

Bug: 7291287

Conflicts:

	libc/bionic/malloc_debug_common.cpp

Change-Id: Ib8780db72ba0114ebdb24768537da74bbb61f354