repair char-foldcase for some single-character special cases

For example, `(char-foldcase #\x1E9E)` should be `#\xDF`, in contrast
to the `(string-foldcase (string #\x1E9E))` result of "ss". The
character foldings that that are different here correspond to cases
that are "S" status in "CaseFolding.txt".

Thanks to Marc Feeley for noticing and reporting the bug.

Also, repair some dependencies in "s/build.zuo".

mats/5_4.ms

@@ -590,6 +590,8 @@
     (error? (char-foldcase 'a))
     (eqv? (char-foldcase #\a) #\a)
     (eqv? (char-foldcase #\Z) #\z)
+    (eqv? (char-foldcase #\x1e9e) #\xDF)
+    (eqv? (char-foldcase #\x1f8d) #\x1f85)
  )
 
 (mat integer->char

s/build.zuo

@@ -209,7 +209,8 @@
     (append (map at-source
                  (list "debug.ss" "primdata.ss" "layout.ss"))
             (append type-srcs
-                    cpnanopass-srcs)))
+                    cpnanopass-srcs
+                    unicode-srcs)))
 
   (define other-srcs
     ;; files that are used to initialize the compiler
@@ -447,8 +448,7 @@
        ;; independent of whether dependencies changed:
        [:target all (bootall ,@output-headers)
                 ,void]
-       [:target bootall (,@all-srcs ,@(add-patchfile macro-objs) ,nanopass.so ,@type-srcs
-                                    ,@cpnanopass-srcs ,@unicode-srcs)
+       [:target bootall (,@all-srcs ,@(add-patchfile macro-objs) ,nanopass.so)
                 ,(lambda (token)
                    (mkdir-p (at-boot "."))
                    (run-scheme "all at once"

unicode/extract-char-cases.ss

@@ -108,7 +108,7 @@
               [offset (codes->off (caddr fields) n)])
           (chardata-fcchar-set! cdrec offset)
           (chardata-fcstr-set! cdrec offset))))
-    (filter (lambda (fields) (equal? (cadr fields) "C")) data))
+    (filter (lambda (fields) (member (cadr fields) '("C" "S"))) data))
   (for-each 
     (lambda (fields)
       (let ([n (hex->num (car fields))])