Don't hardcode the super partition name.

If a device has logical partitions but does not use a partition called
"super", we will need this to be configurable. Note that the "slot"
argument is currently unused, but will be necessary for update_engine if
there are A and B super partitions.

Bug: 116608795
Test: super partition works
Change-Id: Ieb548a158faeb423f3561230f26d582325efbc6b
diff --git a/fastboot/device/utility.cpp b/fastboot/device/utility.cpp
index 02f6f2c..528abec 100644
--- a/fastboot/device/utility.cpp
+++ b/fastboot/device/utility.cpp
@@ -23,6 +23,7 @@
 
 #include <android-base/file.h>
 #include <android-base/logging.h>
+#include <fs_mgr.h>
 #include <fs_mgr_dm_linear.h>
 #include <liblp/liblp.h>
 
@@ -44,7 +45,7 @@
 
 static bool OpenLogicalPartition(const std::string& name, const std::string& slot,
                                  PartitionHandle* handle) {
-    std::optional<std::string> path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME);
+    std::optional<std::string> path = FindPhysicalPartition(fs_mgr_get_super_partition_name());
     if (!path) {
         return false;
     }
@@ -100,7 +101,7 @@
 
 bool LogicalPartitionExists(const std::string& name, const std::string& slot_suffix,
                             bool* is_zero_length) {
-    auto path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME);
+    auto path = FindPhysicalPartition(fs_mgr_get_super_partition_name());
     if (!path) {
         return false;
     }
@@ -149,7 +150,7 @@
     }
 
     // Next get logical partitions.
-    if (auto path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME)) {
+    if (auto path = FindPhysicalPartition(fs_mgr_get_super_partition_name())) {
         uint32_t slot_number = SlotNumberForSlotSuffix(device->GetCurrentSlot());
         if (auto metadata = ReadMetadata(path->c_str(), slot_number)) {
             for (const auto& partition : metadata->partitions) {