This problem has been around since the early days of computers.
I'm a McEv*** and have found my surname to be spelt Mcev*** and Mc Ev***
just as in your example.

Many documents are still technically incorrect. Both my Irish and Canadian passports are correct, as is my driving licence. However, each of these use all caps and are therefore not problematical.

It appears that many government computer systems simply cannot handle having a cap placed in between lower case letters. Some data entry people seem to have created their own solution by inserting a space after the lower case "c"! You either get the cap, prefixed by a space or the required cap remains lower case!

And before someone asks, yes, I have received mail addressed to Mr. Ev*** with the Mc either omitted or added as a suffix to my Christian name.

I don't think the OP need worry unless travelling to countries where authorities are excessively picky!