Makefile: add platform-specific default mass-storage-gadget directory

[nbuchwitz]

Move the default mass-storage-gadget64 directory path from a hardcoded value in main.c to a build-time configurable variable in the Makefile. On Windows, this defaults to the standard installation path used by the Windows installer. On Unix systems, the behavior remains unchanged.

This allows rpiboot to be invoked without the -d parameter on Windows.

Fixes: #342

[timg236]

This looks like a useful change.

N.B. Now that mass-storage-gadget64 is working on PiZero2, CM3* I'm planning to make this the default instead of the VPU firmware implemenation. I think the outlier is possibly PiZero.

[nbuchwitz]

This looks like a useful change.

N.B. Now that mass-storage-gadget64 is working on PiZero2, CM3* I'm planning to make this the default instead of the VPU firmware implemenation. I think the outlier is possibly PiZero.

That's good to hear. We've seen an increasing number of issues raised by our users, which have overlooked the bat files on Windows and are trying to use rpiboot.exe as before. So I really hope that this will make it a bit better for all the Windows.

btw: Wouldn't it make sense to make a new "official" release on the github project? Last release was when CM4S was introduced.

[timg236]

This looks like a useful change.
N.B. Now that mass-storage-gadget64 is working on PiZero2, CM3* I'm planning to make this the default instead of the VPU firmware implemenation. I think the outlier is possibly PiZero.

That's good to hear. We've seen an increasing number of issues raised by our users, which have overlooked the bat files on Windows and are trying to use rpiboot.exe as before. So I really hope that this will make it a bit better for all the Windows.

btw: Wouldn't it make sense to make a new "official" release on the github project? Last release was when CM4S was introduced.

Yes. Actually, I think we can drop the .exe from the Git repo and just attach it to a release to make the git shallow clone a bit quicker.