[OE-core] SDK and external toolchain

[Marcin Juszkiewicz]

I did not tested it without external toolchain yet and have
no idea is it good way at all. 

diff --git a/meta/classes/toolchain-scripts.bbclass b/meta/classes/toolchain-scripts.bbclass
index 050e799..f5801a8 100644
--- a/meta/classes/toolchain-scripts.bbclass
+++ b/meta/classes/toolchain-scripts.bbclass
@@ -142,7 +142,7 @@ toolchain_create_sdk_env_script_for_installer () {
 #we get the cached site config in the runtime
 TOOLCHAIN_CONFIGSITE_NOCACHE = "${@siteinfo_get_files(d, True)}"
 TOOLCHAIN_CONFIGSITE_SYSROOTCACHE = "${STAGING_DATADIR}/${TARGET_SYS}_config_site.d"
-TOOLCHAIN_NEED_CONFIGSITE_CACHE = "${TCLIBC} ncurses"
+TOOLCHAIN_NEED_CONFIGSITE_CACHE = "ncurses"
 
 #This function create a site config file
 toolchain_create_sdk_siteconfig () {
@@ -161,6 +161,11 @@ toolchain_create_sdk_siteconfig () {
                        cat ${TOOLCHAIN_CONFIGSITE_SYSROOTCACHE}/${sitefile}_config >> $siteconfig
                fi
        done
+       if [ "${TCMODE}" = "default" ]; then
+               if [ -r ${TOOLCHAIN_CONFIGSITE_SYSROOTCACHE}/${TCLIBC}_config ]; then
+                       cat ${TOOLCHAIN_CONFIGSITE_SYSROOTCACHE}/${TCLIBC}_config >> $siteconfig
+               fi
+       fi
 }
 # The immediate expansion above can result in unwanted path dependencies here
 toolchain_create_sdk_siteconfig[vardepsexclude] = "TOOLCHAIN_CONFIGSITE_SYSROOTCACHE"