lmb: change the return code on lmb_alloc_addr()

lmb: change the return code on lmb_alloc_addr()

Ben reports a failure to boot the kernel on hardware that starts its
physical memory from 0x0.
The reason is that lmb_alloc_addr(), which is supposed to reserve a
specific address, takes the address as the first argument, but then also
returns the address for success or failure and treats 0 as a failure.

Since we already know the address change the prototype to return an int.

Reported-by: Ben Schneider <ben@bens.haus>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Tested-by: Ben Schneider <ben@bens.haus>
Reviewed-by: Sughosh Ganu <sughosh.ganu@linaro.org>