[PATCH] uml: Remove ubd-mmap support

Finally rip out the ubd-mmap code, which turned out to be broken by design.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>