Disable packaged-staging for cross-linkage/staging-linkage and external-poky-toolchain

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

meta/classes/packaged-staging.bbclass

@@ -48,6 +48,9 @@ python () {
     if bb.data.inherits_class('image', d):
         pstage_allowed = False
 
+    if bb.data.getVar('PSTAGING_DISABLED', d, True) == "1":
+        pstage_allowed = False
+
     # Add task dependencies if we're active, otherwise mark packaged staging
     # as inactive.
     if pstage_allowed:

meta/packages/meta/cross-linkage_1.0.bb

@@ -16,6 +16,8 @@ do_compile () {
 	:
 }
 
+PSTAGING_DISABLED = "1"
+
 do_install() {
 	install -d ${CROSS_DIR}/${TARGET_SYS}/
 	if [ -e ${CROSS_DIR}/${TARGET_SYS}/include ]; then

meta/packages/meta/external-poky-toolchain.bb

@@ -14,6 +14,8 @@ PACKAGES_DYNAMIC = "glibc-gconv-*"
 INHIBIT_DEFAULT_DEPS = "1"
 PR = "r1"
 
+PSTAGING_DISABLED = "1"
+
 do_install() {
 	if [ ! -e  ${prefix}/environment-setup ]; then
 		echo "The Poky toolchain could not be found in ${prefix}!"

meta/packages/meta/staging-linkage_1.0.bb

@@ -16,6 +16,8 @@ do_compile () {
 	:
 }
 
+PSTAGING_DISABLED = "1"
+
 do_install () {
 	if [ -e ${STAGING_DIR_HOST}${base_libdir} ]; then
 		cp -pPRr ${STAGING_DIR_HOST}${base_libdir}/* ${STAGING_LIBDIR}