Fix wrong drive format on Unix

src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.FormatInfo.cs

@@ -91,18 +91,19 @@ private static unsafe int GetFormatInfoForMountPoint(string name, out string for
                     fields.MoveNext(); // Skip Parent ID
                     fields.MoveNext(); // Skip Major:Minor
                     fields.MoveNext(); // Skip Root
+                    fields.MoveNext(); // Move next to MountPoint field
 
-                    if (!MemoryExtensions.Equals(line[fields.Current], name, StringComparison.Ordinal)) continue;
+                    if (!line[fields.Current].Equals(name, StringComparison.Ordinal)) continue;
 
                     // Skip to the separator which is end of optional fields (Field 8)
-                    while (fields.MoveNext() && !MemoryExtensions.Equals(line[fields.Current], "-", StringComparison.Ordinal));
+                    while (fields.MoveNext() && !line[fields.Current].Equals("-", StringComparison.Ordinal)) ;
 
                     fields.MoveNext();
                     format = line[fields.Current].ToString();
 
                     fields.MoveNext();
                     type = GetDriveType(line[fields.Current].ToString());
-                    
+
                     return 0;
             }
             catch { /* ignored */ }