[PATCH] IB uverbs: add mthca ABI header

Add the mthca_user.h header file, which defines the device-specific ABI used
by the mthca low-level driver for kernel/user communication.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>