Remove oldmask from the sigcontext structure. Also update wmask
and windowstart when we flush the AR registers to stack.
Signed-off-by: NChris Zankel <chris@zankel.net>

The non-rt signal handling was never really used, so we don't break
anything. This patch also cleans up the signal stack-frame to make
it independent from the processor configuration. It also improves
the method used for controlling single-stepping. We now save and
restore the 'icountlevel' register that controls single stepping
and set or clear the saved state to enable or disable it.
Signed-off-by: NChris Zankel <chris@zankel.net>

The attached patches provides part 6 of an architecture implementation for the
Tensilica Xtensa CPU series.
Signed-off-by: NChris Zankel <chris@zankel.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>