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 -durN strace-4.5.19.orig/syscall.c strace-4.5.19/syscall.c

--- strace-4.5.19.orig/syscall.c	2009-10-12 21:54:21.000000000 +0200

+++ strace-4.5.19/syscall.c	2009-10-28 18:47:18.000000000 +0100

@@ -1022,6 +1022,15 @@

 		/*

 		 * Note: we only deal with only 32-bit CPUs here.

 		 */

+

+		if (!(tcp->flags & TCB_INSYSCALL) &&

+		    (tcp->flags & TCB_WAITEXECVE)) {

+			/* caught a fake syscall from the execve's exit */

+			tcp->flags &= ~TCB_WAITEXECVE;

+			return 0;

+		}

+

+

 		if (regs.ARM_cpsr & 0x20) {

 			/*

 			 * Get the Thumb-mode system call number