Moving some KSP utils to compiler-util

[WhosNickDoglio]

👋

I'm currently working on migrating an Anvil plugin to support KSP and this work, there's a number of KSP util functions in the compiler module that are would be useful. I'm looking at functions in these files:

• https://github.com/ZacSweers/anvil/blob/main/compiler/src/main/java/com/squareup/anvil/compiler/codegen/ksp/KspUtil.kt
• https://github.com/ZacSweers/anvil/blob/main/compiler/src/main/java/com/squareup/anvil/compiler/codegen/dagger/DaggerGenerationUtils.kt

Would you be open to a PR moving these into the compiler-utils module?

[ZacSweers]

Yep!