Fix the ASan ioctl.cc test when using COMPILER_RT_DEBUG=On

In debug mode (COMPILER_RT_DEBUG=On), we still build with -fomit-frame-pointer and wrap_ioctl doesn't set up a proper stack frame.  In release mode it does, because ioctl_common_pre gets inlined into wrap_ioctl and it uses the COMMON_INTERCEPTOR_READ_RANGE macro which in the end calls GET_CURRENT_FRAME and that forces the compiler to generate a stack frame for the function.

Not having a proper stack frame breaks the unwinder.  This patch forces to generate a frame pointer (via ENABLE_FRAME_POINTER macro).

Reviewed at http://reviews.llvm.org/D7815

llvm-svn: 230318