classes, conf, lib: Add support for powerpc64le

LE is default for modern powerpc64, power8+

PowerPC64 Little Endian Linux ABI specifies Power8 as the minimum ISA.
The basic ABI can run on earlier versions of the 64 bit PowerPC ISA,
but it was helpful to define a new, minimum instruction set for Linux
distribution releases during the switch to Little Endian.

(From OE-Core rev: b9c73fb6d1afb3367d871a3d6bf7d0d6a53968a9)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/meson.bbclass

@@ -45,7 +45,7 @@ def meson_cpu_family(var, d):
     arch = d.getVar(var)
     if arch == 'powerpc':
         return 'ppc'
-    elif arch == 'powerpc64':
+    elif arch == 'powerpc64' or arch == 'powerpc64le':
         return 'ppc64'
     elif arch == 'armeb':
         return 'arm'