linux-renesas_%.bbappend: Fix ath9k_htc.cfg and rtl_sdr.cfg

Files ath9k_htc.cfg and rtl_sdr.cfg are provided
by linux-agl.inc. As of the moment there is no need
linux-renesas_%.bbappend also to provide them and
furthermore this patches fixes the kernel build.

Bug-AGL: SPEC-1152

Change-Id: I29ddac799469e0a3107037bb11918c228d10b5db
Signed-off-by: Leon Anavi <leon.anavi@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/12297
Tested-by: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-build: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>