[Feature Request][mojo-stdlib] Add "_" as a words separator to methods in TargetInfo

[gryznar]

Recently methods from TargetInfo:

• alignof,
• bitwidthof,
• simdwidthof,
• simdbitwidth,
• simdbytewidth,
• sizeof

were normalized to remove "_" from them.
However this convention hurts readability in my opinion. Everything just blends together. Compare:

• simdwidthof
• simdbitwidth
• simdbytewidth

It is not easy do determine which of those 3 was used at first glance.

I propose to add "_" as a word separator. Total length won't be increased so much (at most 2 chars), but readability "at first glance" will increase a lot.

Most methods in Mojo also have separated words, so here is no big reason for exception, especially due to the fact, that mostly 3 words are combined.

[gryznar]

Bumping up. This will be also more consistent with the nqming convention in other packages