Fix memory error when dumping timings.
Fix memory error when dumping timings.

Use the pass name instead of a stack allocated std::string.

Change-Id: Ic87cf9cb7cc3c7bd847cc69c9aa1203d07136062
treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst