v4.5.1

Changelog:

• Fixed the file loader, it should now detect all sizes properly.
• Added a check for os0:e2x_ckldr.skprx - it will no longer bootloop if the file is not present.
  • It could anyways be skipped with VOLDOWN.

This is the last release for 3.60 bootloaders, all future releases will be 3.65 only.