(stmtch, mineq): Document. Move declaration from prototypes.h to

match.h.  Use plain char instead of s_char.  The code has several
thousand type errors due to s_char vs plain char; s_char must go.
(stmtch): Rewrite for clarity.

include/match.h

@@ -34,6 +34,8 @@
 #ifndef _MATCH_H_
 #define _MATCH_H_
 
+#include <stddef.h>
+
 /* returned by stmtch() */
 #define M_IGNORE        -3
 #define M_NOTUNIQUE	-2
@@ -45,4 +47,7 @@
 #define ME_PARTIAL	1
 #define ME_EXACT	2
 
+extern int stmtch(char *, void *, ptrdiff_t, size_t);
+extern int mineq(char *, char *);
+
 #endif /* _MATCH_H_ */