configs: Rename qcs9100_defconfig to qcom_qcs9100_defconfig

To align with the naming convention used for Qualcomm platforms in
U-Boot, renamed the defconfig file from qcs9100_defconfig to
qcom_qcs9100_defconfig.

Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>
Reviewed-by: Casey Connolly <casey.connolly@linaro.org>
Link: https://patch.msgid.link/20250630070040.734486-2-balaji.selvanathan@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>

diff --git a/configs/qcs9100_defconfig b/configs/qcom_qcs9100_defconfig
similarity index 100%
rename from configs/qcs9100_defconfig
rename to configs/qcom_qcs9100_defconfig