Fix dup af+ removing function from hts

[thestr4ng3r]

Detailed description

This fixes the following issue:

$ r2 /bin/ls
> af;.afi*
# cannot add basic block errors
> af;.afi*
# no errors at all
> af;.afi*
# cannot add basic block errors again

or more narrowed down:

[0x00000000]> af+ 0x1337 func
[0x00000000]> af+ 0x1337 func
Invalid function name 'func' at 0x00001337
Cannot add function (duplicated)
[0x00000000]> af+ 0x1337 func
[0x00000000]> af+ 0x1337 func
Invalid function name 'func' at 0x00001337
Cannot add function (duplicated)
[0x00000000]>

The expected behavior is that all subsequent af+ calls show the error.
This is however not only about error printing, in fact the duplicated af+ would remove the function from the address and name hashtables which is a problem.

Closing issues

#15453 (doesn't directly solve the project-related issue but I think we can close with r2db coming soon^TM)

[radare]

looks red. pls confirm if the referenced issue can be closed

[radare]

[thestr4ng3r]

Yeah it slightly changes analysis behavior. But that is because before there were some "leaked" duplicate functions at the same address, so it is more correct now.

Well as I have written, the issue itself is about projects, which is not fixed by this. But since trying to fix current projects at this point would be a waste of time, I think we can close it.

[radare]

.