powerpc: Add VSX context save/restore, ptrace and signal support

This patch extends the floating point save and restore code to use the
VSX load/stores when VSX is available.  This will make FP context
save/restore marginally slower on FP only code, when VSX is available,
as it has to load/store 128bits rather than just 64bits.

Mixing FP, VMX and VSX code will get constant architected state.

The signals interface is extended to enable access to VSR 0-31
doubleword 1 after discussions with tool chain maintainers.  Backward
compatibility is maintained.

The ptrace interface is also extended to allow access to VSR 0-31 full
registers.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --cc arch/powerpc/kernel/entry_64.S
Simple merge

diff --cc arch/powerpc/kernel/fpu.S
Simple merge

diff --cc arch/powerpc/kernel/head_64.S
Simple merge

diff --cc arch/powerpc/kernel/misc_64.S
Simple merge

diff --cc arch/powerpc/kernel/ppc32.h
Simple merge

diff --cc arch/powerpc/kernel/ppc_ksyms.c
Simple merge

diff --cc arch/powerpc/kernel/process.c
Simple merge

diff --cc arch/powerpc/kernel/ptrace.c
Simple merge

diff --cc arch/powerpc/kernel/signal_32.c
Simple merge

diff --cc arch/powerpc/kernel/signal_64.c
Simple merge

diff --cc arch/powerpc/kernel/traps.c
Simple merge

diff --cc include/asm-powerpc/elf.h
Simple merge

diff --cc include/asm-powerpc/ptrace.h
Simple merge

diff --cc include/asm-powerpc/reg.h
Simple merge

diff --cc include/asm-powerpc/sigcontext.h
Simple merge

diff --cc include/asm-powerpc/system.h
Simple merge