Bls precompile: Use MUL for single point MSM

[Marchhill]

Changes

• For MSM with a single point use MUL

Types of changes

What types of changes does your code introduce?

• Bugfix (a non-breaking change that fixes an issue)
• New feature (a non-breaking change that adds functionality)
• Breaking change (a change that causes existing functionality not to work as expected)
• Optimization
• Refactoring
• Documentation update
• Build-related changes
• Other: Description

Testing

Requires testing

• Yes
• No

If yes, did you write tests?

• Yes
• No

Notes on testing

Covered by state tests

Documentation

Requires documentation update

• Yes
• No

Requires explanation in Release Notes

• Yes
• No

[Marchhill]

Note: duplicated MUL code as MUL will be removed here: #7932

[MarekM25]

Looks good. Do we need this though? MSM should be good enough?

[Marchhill]

Looks good. Do we need this though? MSM should be good enough?

It's more efficient this way as we don't have overhead of MSM