Placate a number of `syntax-check' verifications.

- "filesystem" -> "file system"
  - remove doubled words
  - use EXIT_* macros instead of literal numbers
  - update `syntax-check' exclusion files

module/system/base/compile.scm

@@ -93,7 +93,7 @@
 ;;; This function is among the trickiest I've ever written. I tried many
 ;;; variants. In the end, simple is best, of course.
 ;;;
-;;; After turning this around a number of times, it seems that the the
+;;; After turning this around a number of times, it seems that the
 ;;; desired behavior is that .go files should exist in a path, for
 ;;; searching. That is orthogonal to this function. For writing .go
 ;;; files, either you know where they should go, in which case you tell