Support "." in cpu and arch variant names

cortex-a53.a57 is a valid cpu variant, and needs to be translated to
cortex_a53_a57 when used as a field name.  Replace
dashToUnderscoreReplacer with a replacer that also converts "." to "_".

Change-Id: I1c496249b50d8e3a8d2bd830bc890f43ad9ee29e
1 file changed