All asm/ipc.h files do only #include <asm-generic/ipc.h>.

This patch therefore removes all include/asm-*/ipc.h files and moves the
contents of include/asm-generic/ipc.h to include/linux/ipc.h.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>