hadrian/hie-bios: pass -j to hadrian

This commit passes -j to hadrian in the hadrian/hie-bios scripts. When
the user starts HLS in a fresh clone that has just been configured, it
takes quite a while for hie-bios to pick up the ghc flags and start
actual indexing, due to the fact that the hadrian build step defaulted
to -j1, so -j speeds things up and improve HLS user experience in GHC.
Also add -j flag to .ghcid to speed up ghcid, and sets the Windows
build root to .hie-bios which also works and unifies with other
platforms, the previous build root _hie-bios was missing from
.gitignore anyway.