[one-cmds/one-import] Fix "--verbose" option

[seanshpark]

one-import and one-import-* doesn't provide --verbose option.

• one-import-onnx does have --verbose but changing TF_CPP_MIN_LOG_LEVEL doesn't seem to work

these have sys.tracebacklimit = 0 to silence unnecessary messages,
but for debugging this gives no help.

for each import tools, let's enable possible logs when verbose option is on.

[seanshpark]

sys.tracebacklimit default is 1000

• https://docs.python.org/3/library/sys.html#sys.tracebacklimit

[seanshpark]

onecc --verbose -C model.cfg

doesn't seem to propagate to one-import-onnx

• change is [one-cmds] Apply verbose option to one-import-onnx #7506
• @jyoungyun , is there something wrong with above command for this?

[seanshpark]

TF_CPP_MIN_LOG_LEVEL doesn't seem to work

It's now TF_CPP_MAX_VLOG_LEVEL

• have to set TF_CPP_MAX_VLOG_LEVEL=3 to show logs

---

https://github.com/tensorflow/tensorflow/blob/2e076fec019b7c816329282fb1a7408e6f0d1185/tensorflow/python/util/vlog_test.py#L20

import os
os.environ["TF_CPP_MAX_VLOG_LEVEL"] = "5"
os.environ["TF_CPP_MIN_LOG_LEVEL"] = "0"

this test sets to 5 ...