arch/powerpc: add powerpc64le support

Technically, I don't forbid powerpcle support either, but I'm not sure that
there is any library/compiler support for that at the moment (though the hw
technically makes it possible).

powerpc64le needs glibc 2.19 and gcc 4.9. I haven't looked into the support
tools, but at least gdb 7.5 is too old (7.7.1 definitely has support).

Also make powerpc64 non-experimental. It's practically old at this point.

Signed-off-by: Cody P Schafer <dev@codyps.com>
[yann.morin.1998@free.fr: use ${target_endian_le} and ${target_bits_64}]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Message-Id: <64bfbbced9dd8f62e0d6.1399801945@gun>
Patchwork-Id: 347775

 diff -dur strace-4.5.15.orig/net.c strace-4.5.15/net.c

 --- strace-4.5.15.orig/net.c	2006-12-13 20:57:23.000000000 +0100

 +++ strace-4.5.15/net.c	2007-07-14 19:29:36.000000000 +0200

 @@ -800,8 +800,12 @@

  #ifdef SOL_PACKET

  static const struct xlat sockpacketoptions[] = {

 +#if defined(PACKET_ADD_MEMBERSHIP)

  	{ PACKET_ADD_MEMBERSHIP,	"PACKET_ADD_MEMBERSHIP"	},

 +#endif

 +#if defined(PACKET_DROP_MEMBERSHIP)

  	{ PACKET_DROP_MEMBERSHIP,	"PACKET_DROP_MEMBERSHIP"},

 +#endif

  #if defined(PACKET_RECV_OUTPUT)

  	{ PACKET_RECV_OUTPUT,		"PACKET_RECV_OUTPUT"	},

  #endif