Merged in masayuki2009/nuttx.nuttx/fix_signal_handing_for_smp (pull request #599)

Fix signal handing for smp

* sched/signal: Remove SMP related logic in sig_dispatch.c

    This change prevents from a deadlock in up_schedulesigaction.c
    where inter-CPU signal handling is actually implemented.

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* arch/arm/src/armv7-m: Fix signal handling for SMP

    In previous implementation, signal handling for SMP was incorrect.
    Thus, for example, if an inter-CPU signal happened an incorret tcb
    was signaled and caused ASSERT().

    This change fixes the issues and works for both inter-CPU signal
    handling and signal handling on the same CPU.

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

Approved-by: Gregory Nutt <gnutt@nuttx.org>