Replace func name with regex for update test scripts

The patch adds an argument to update test scripts, such as update_cc_test_checks, for replacing a function name matching a regex. This functionality is needed to match generated function signatures that include file hashes. Example:

The function signature for the following function:

`__omp_offloading_50_b84c41e__Z9ftemplateIiET_i_l30_worker`

with `--replace-function-regex "__omp_offloading_[0-9]+_[a-z0-9]+_(.*)"` will become:

`CHECK-LABEL: @{{__omp_offloading_[0-9]+_[a-z0-9]+__Z9ftemplateIiET_i_l30_worker}}(`

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D97107