Fix check CC compiler variable in configure

[ruota]

If you use a compiler with abs path there are some issues, e.g. if my path contains the word "piccolo" the script enable some flags of icc compiler because "piccolo" contains "icc".

[the-knights-who-say-ni]

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[ruota]

I signed the CLA with bugs.python.org username: ruota

[ruota]

I want to add labels "skip news" and "skip issue"

[grimreaper]

Ref #6783 #6782 #6781 #6780 #6771

[ruota]

I don't think these issues are related

[grimreaper]

they are related because they are affecting configure.ac - not directly related to your bug though.

[csabella]

Thank you for your interest in improving CPython. This is not a trivial change and would require an issue to be created on bugs.python.org. If you are interested in pursuing this, please open an issue on the bug tracker and reopen this pull request with the bpo number in the title as per the devguide. Also, please resolve the merge conflicts once reopened. Thanks!