musl-nativesdk: add SDKLIBC to BUILDCFG_VARS
musl-nativesdk: add SDKLIBC to BUILDCFG_VARS

Signed-off-by: Christopher Larson <4c8c411260e601995081b113a5ef94a26eff2b25@mentor.com>

kergoth/meta-kergoth-wip,kergoth/meta-kergoth-wip