Install cross-packages into the native sysroot

Cross is no longer required so can go away, we now install cross packages into
the native sysroot and use them from there.

This patch includes updates to classes and some recipes which reference
CROSS_DIR. Others still need fixing an image can be built and run with this
patch applied.

Signed-off-by: Joshua Lock <josh@linux.intel.com>

meta/classes/nativesdk.bbclass

@@ -18,8 +18,6 @@ python () {
 #STAGING_DIR_HOST = "${STAGING_DIR}/${HOST_SYS}-nativesdk"
 #STAGING_DIR_TARGET = "${STAGING_DIR}/${BASEPKG_TARGET_SYS}-nativesdk"
 
-CROSS_DIR = "${TMPDIR}/cross/${HOST_ARCH}"
-
 HOST_ARCH = "${SDK_ARCH}"
 HOST_VENDOR = "${SDK_VENDOR}"
 HOST_OS = "${SDK_OS}"