Cleanup: move clear_table() to divesite.c

There were two declaration of clear_table(), one in dive.h and one
in parse.h. The definition was in parse.c. Since the parser doesn't
even use the function, move the function and its declaration to
divelist.[ch] and remove the redundant declaration in dive.h.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

core/parse.c

@@ -70,16 +70,6 @@ int trimspace(char *buffer)
 	return size;				// return string length
 }
 
-/*
- * Clear a dive_table
- */
-void clear_table(struct dive_table *table)
-{
-	for (int i = 0; i < table->nr; i++)
-		free(table->dives[i]);
-	table->nr = 0;
-}
-
 /*
  * Add a dive into the dive_table array
  */