msm: smsm: define new bit - SMSM_ERR_SRV_READY

SMSM_ERR_SRV_READY indicates when the hardware watchdog and error handling
modules on the remote subsystem are initialized and active.

Used by the subsystem restart framework to determine if a remote restart
has been sucessful within the time limit allowed.

Change-Id: I579e49a6e66a72a4daad2ab97681112dc0bcf2ea
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>