Respect ro.boot.fstab_suffix in swapon_all

While mount_all and umount_all were updated to use ro.boot.fstab_suffix,
I neglected to update swapon_all. Trivially copied from umount_all.

Bug: 142424832
Change-Id: Icd706fe7a1fe16c687cd2811b0a3158d7d2e224e
Merged-In: Icd706fe7a1fe16c687cd2811b0a3158d7d2e224e
diff --git a/init/util.cpp b/init/util.cpp
index 40f24b1..aec3173 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -654,11 +654,22 @@
     return std::pair(flag, paths);
 }
 
+Result<std::string> ParseSwaponAll(const std::vector<std::string>& args) {
+    if (args.size() <= 1) {
+        if (SelinuxGetVendorAndroidVersion() <= __ANDROID_API_Q__) {
+            return Error() << "swapon_all requires at least 1 argument";
+        }
+        return {};
+    }
+    return args[1];
+}
+
 Result<std::string> ParseUmountAll(const std::vector<std::string>& args) {
-    if (SelinuxGetVendorAndroidVersion() <= __ANDROID_API_Q__) {
-        if (args.size() <= 1) {
+    if (args.size() <= 1) {
+        if (SelinuxGetVendorAndroidVersion() <= __ANDROID_API_Q__) {
             return Error() << "umount_all requires at least 1 argument";
         }
+        return {};
     }
     return args[1];
 }