[ofa-general] ofed_1_2 git echa problems

[Roland Dreier]

 > In ofed-1.2-alpha we removed do_mmap() from kernel space, which
 > also affects user space in that both kernel and user space components
 > have to be from the same code stream.

I wasn't paying enough attention to this change.  If you break
compatibility between userspace and kernel space, you should adjust
your kernel driver's uverbs_abi_ver (which I think you did with the
do_mmap()) removal, and then test the version in the userspace
library, so that it can fail gracefully when it detects a too-new
kernel that it doesn't know how to handle.

 - R.