### Please describe the problem.
I get error while attempting to create an adb special remote
Problem appears to be with gvfs (mtp)  mount point that my phone is getting mounted to.

### What steps will reproduce the problem?
Attach android phone to computer via USB. (eg Pixel3A, Samsung Galaxy S6  etc.)
Phone mounts using gvfs-mtp. (GNOME virt file system)
 Specifically in my case at the following path:

/run/user/1000/gvfs/mtp\:host\=Google_Pixel_3a_94MBYKEOEJS/Internal\ shared\ storage/DCIM

Attempt to create adb special remote as follows:

git annex initremote android type=adb 
androiddirectory=/run/user/1000/gvfs/mtp\:host\=Google_Pixel_3a_94MBYKEOEJS/Internal\ shared\ storage/DCIM
encryption=none exporttree=yes importtree=yes 

Results in following error message:
initremote android git-annex: adb: createProcess: runInteractiveProcess: exec: does not exist (No such file or directory) failed git-annex: initremote: 1 failed

I can successfully 'cd' into the path via xterm and browse the phone's DCIM directory etc as normal
so the path itself if fine. I also tried enclosing the dir name in quotes, double quotes etc but that didn't help
Also tried by creating a symbolic link to the path name and specifying the link name, but no joy 
I was hoping that it was the ":" between  mtp and host that was the issue) 

I have also attempted just to use the directory special remote as well - but I get same error.



### What version of git-annex are you using? On what operating system?
8.20200226  (but I have also seen same issue on earlier ver 7) 
I upgraded to 8 in hope of rectifying the issue.

### Please provide any additional information below.

Running Debian 10.3


### Have you had any luck using git-annex before? 
Yes, have been using git-annex successfully for several years, but this is my first attempt at using the adb special remote.

Thanks
M.


> [[notabug|done]]
