Restructure Salvator-x .inc files

Restructure Salvator-x .inc files

This commit restructure the .inc files relate to H3/M3 Salvator-x boards.

Bug-AGL: SPEC-4808

Signed-off-by: Hau Vo <hau.vo.ra@renesas.com>
Change-Id: I9e01f61f75010c1cbf54feec30422855b43cf051
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/29175
Reviewed-by: Harunobu Kurokawa <harunobu.kurokawa.dn@renesas.com>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
(cherry picked from commit 979598c6e9b855cec0ff56c95eae0d47e9c0e21a)
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/29200