kernel: Fix QA buildpaths warning for kernel modules
CFLAGS is unset during kernel_do_compile and thus the default build
path substitutions in DEBUG_PREFIX_MAP are missing.
To enhance reproducible build for kernel modules, such as lttng-modules
and cryptodev-module, this patch appends them, plus substitution of
STAGING_KERNEL_DIR, to KERNEL_CC.
Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
