fixup! fscache: fscache takes an initial size

Fix a copy-paste bug at the end of `cmd_add()`: the cleanup site called
`enable_fscache(0)` again instead of `disable_fscache()`, leaking the
refcount. Harmless in a one-shot process today, but it confuses the
matching enable/disable contract that callers and reviewers expect.

Signed-off-by: Anthony Shaw <anthonyshaw@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: Anthony Shaw

builtin/add.c

@@ -609,6 +609,6 @@ int cmd_add(int argc,
 	free(ps_matched);
 	dir_clear(&dir);
 	clear_pathspec(&pathspec);
-	enable_fscache(0);
+	disable_fscache();
 	return exit_status;
 }