Renames boot-debug-*.img in GSI targets

Those boot-debug-*.img is used with `repack_bootimg` for a
vendor_boot-debug.img in VTS setup. It is not for GKI boot.img
release.

  https://source.android.com/compatibility/vts/vts-on-gsi#repacking

Renames boot-debug-*.img to boot-with-debug-ramdisk-*.img to
avoid confusion with the official GKI boot.img release.

Bug: 200878300
Test: `lunch gsi_arm64-user` then `make bootimage_debug`
Change-Id: Ia1f6ba847d5b7409fb7a8534432484d2aa972494