avr32: Fix sigaltstack behaviour
avr32: Fix sigaltstack behaviour

A signal handler should be able to change the signal stack used for the
next signal by altering the ucontext_t passed as a parameter to the
handler. This does not currently work on avr32 since it doesn't update
the in-kernel signal context from the ucontext_t upon signal handler
return.

Fix it by adding a call to do_sigaltstack() from sys_rt_sigreturn(),
bringing it in line with most other architectures.

Signed-off-by: Martin Koegler <ea56f0187842ce0af18f0283b5f003697482ffdd@auto.tuwien.ac.at>
[af8c0cf3411930951fa86926b241df32af99fdb9@atmel.com: changed patch description]
Signed-off-by: Haavard Skinnemoen <af8c0cf3411930951fa86926b241df32af99fdb9@atmel.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs