board/qualcomm: Introduce TF-A and OP-TEE config fragment

board/qualcomm: Introduce TF-A and OP-TEE config fragment

Recently upstream TF-A/OP-TEE has started gaining support for Qcom
platforms. RB3Gen2 being the first one and more to come. U-Boot in
corresponding boot flow is packaged as a position independent executable.

So, lets add a generic U-Boot config fragment for Qcom platforms to
support TF-A/OP-TEE based TrustZone stack. Build command:

$ ./scripts/kconfig/merge_config.sh \
       configs/qcom_defconfig \
       board/qualcomm/tfa-optee.config
$ make -j`nproc` DEVICE_TREE=qcom/qcs6490-rb3gen2

For more information refer here:
https://trustedfirmware-a.readthedocs.io/en/latest/plat/qti/rb3gen2.html

Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Reviewed-by: Casey Connolly <casey.connolly@linaro.org>
Link: https://patch.msgid.link/20260127062341.723966-4-sumit.garg@kernel.org
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>