perf trace: Decode architecture-specific signal numbers

perf trace: Decode architecture-specific signal numbers

commit 02c5bb4a352a4cca56e9b5d3a2a57d61062eb2e1 upstream.

SIGSTKFLT is not defined on alpha, mips or sparc.

SIGEMT and SIGSWI are defined on some architectures and should be
decoded here if so.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 8bad5b0abfdb ('perf trace: Beautify signal number arg in several syscalls')
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391648441.3003.101.camel@deadeye.wl.decadent.org.uk
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>