Git core config cannot be picked up from global config

bug: b/253329946
Change-Id: I0ffd146087a68289f0f9d84dea8cddd2d6bd6393
Reviewed-on: https://fuchsia-review.googlesource.com/c/jiri/+/864320
Commit-Queue: Yuping Zhai <yupingz@google.com>
Reviewed-by: Nathan Mulcahey <nmulcahey@google.com>
diff --git a/cmd/jiri/init.go b/cmd/jiri/init.go
index 5915b81..dda58d2 100644
--- a/cmd/jiri/init.go
+++ b/cmd/jiri/init.go
@@ -164,7 +164,7 @@
 		}
 	}
 
-	gitConfigSubm, err := jiri.GitGlobalConfig("jiri.enableSubmodules")
+	gitConfigSubm, err := jiri.GitGetConfig("jiri.enableSubmodules")
 	if len(gitConfigSubm) != 0 {
 		if _, err := strconv.ParseBool(gitConfigSubm); err != nil {
 			return fmt.Errorf("'jiri.enableSubmodules' from git config should be true or false")
diff --git a/x.go b/x.go
index 17cd2c7..7b10e8f 100644
--- a/x.go
+++ b/x.go
@@ -97,8 +97,8 @@
 	return c, nil
 }
 
-func GitGlobalConfig(key string) (string, error) {
-	cmd := exec.Command("git", "config", "--global", key)
+func GitGetConfig(key string) (string, error) {
+	cmd := exec.Command("git", "config", "--get", key)
 	out, err := cmd.Output()
 	if err != nil {
 		return "", err