treewide: deprecate git_config_maybe_bool, use git_parse_maybe_bool

The only difference between these is that the former takes an argument
`name` which it ignores completely. Still, the callers are quite careful
to provide reasonable values for it.

Once in-flight topics have landed, we should be able to remove
git_config_maybe_bool. In the meantime, document it as deprecated in the
technical documentation. While at it, document git_parse_maybe_bool.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/submodule-config.c b/submodule-config.c
index 9345390..0fcdb39 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -213,7 +213,7 @@ static struct submodule *lookup_or_create_by_name(struct submodule_cache *cache,
 static int parse_fetch_recurse(const char *opt, const char *arg,
 			       int die_on_error)
 {
-	switch (git_config_maybe_bool(opt, arg)) {
+	switch (git_parse_maybe_bool(arg)) {
 	case 1:
 		return RECURSE_SUBMODULES_ON;
 	case 0:
@@ -237,7 +237,7 @@ int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 static int parse_push_recurse(const char *opt, const char *arg,
 			       int die_on_error)
 {
-	switch (git_config_maybe_bool(opt, arg)) {
+	switch (git_parse_maybe_bool(arg)) {
 	case 1:
 		/* There's no simple "on" value when pushing */
 		if (die_on_error)