CLEANUP: remove unused setBoolean()

setBoolean() had no callers anywhere in the tree.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: JanWielemaker

src/pl-util.c

@@ -310,16 +310,6 @@ notImplemented(char *name, int arity)
 }
 
 
-foreign_t
-setBoolean(int *flag, term_t old, term_t new)
-{ if ( !PL_unify_bool_ex(old, *flag) ||
-       !PL_get_bool_ex(new, flag) )
-    fail;
-
-  succeed;
-}
-
-
 foreign_t
 setInteger(int *flag, term_t old, term_t new)
 { GET_LD

src/pl-util.h

@@ -51,7 +51,6 @@ char *		sourceFileName(SourceFile sf);
 char *		generationName(gen_t gen);
 int		clauseNo(Clause clause, gen_t gen);
 int		notImplemented(char *name, int arity);
-foreign_t	setBoolean(int *flag, term_t o, term_t n);
 foreign_t	setInteger(int *val, term_t old, term_t new);
 const char *	atom_summary(atom_t name, unsigned int maxlen);
 const char *	string_summary(word name, unsigned int maxlen);