mb/intel/mtlrvp: Add initial code for mtlrvp_p_ext_ec variant board

This patch adds the initial code for mtlrvp_p_ext_ec variant board
which includes
1. support for 2 mainboards (Chrome EC and Windows EC) by
adding overridetree.cb to corresponding directory
2. Move devicetree to baseboard/mtlrvp_p
3. Update mainboard name in Kconfig and Kconfig.name
4. Add config option to select corresponding overridetree.cb

Subsequent patches include patch train starting from (CB - 66102)

BUG=b:260654043
TEST=Able to build with the patch and boot the mtlrvp platform with the
subsequent patches

Signed-off-by: Harsha B R <harsha.b.r@intel.com>
Change-Id: I83948aa5e9fcaadee4745e313360773c48142f89
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70346
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Usha P <usha.p@intel.com>

0 files changed, 0 insertions, 0 deletions