Use SourceInfo in Builder error messages when available (backport #2849) (#2852)

* Use SourceInfo in Builder error messages when available (#2849)

* Use SourceInfo in Builder error messages when available

* Use line break instead of semicolon

Co-authored-by: Jack Koenig <jack.koenig3@gmail.com>

Co-authored-by: Jack Koenig <jack.koenig3@gmail.com>
(cherry picked from commit e45be10a

)

# Conflicts:
#	core/src/main/scala/chisel3/Module.scala
#	core/src/main/scala/chisel3/RawModule.scala
#	core/src/main/scala/chisel3/internal/Builder.scala

* Resolve backport conflicts

* Resolve binary compatibility issues

* Undo a change to a protected API
* Waive private classes (they're public in the bytecode because Java
  doesn't have a notion of file private)

* Fix test

---------

Co-authored-by: Daniel Resnick <danielzresnick@gmail.com>
Co-authored-by: Jack Koenig <koenig@sifive.com>