arm64: defconfig: enable DisplayPort altmode support

Enable the DisplayPort altmode, it is required to get DisplayPort output
to work on devices like Qualcomm Robotics RB5 platform.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewd-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Link: https://lore.kernel.org/r/20231011103245.96638-2-dmitry.baryshkov@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Author: lumag

arch/arm64/configs/defconfig

@@ -1044,6 +1044,7 @@ CONFIG_TYPEC_MUX_FSA4480=m
 CONFIG_TYPEC_MUX_NB7VPQ904M=m
 CONFIG_UCSI_CCG=m
 CONFIG_TYPEC_MUX_GPIO_SBU=m
+CONFIG_TYPEC_DP_ALTMODE=m
 CONFIG_MMC=y
 CONFIG_MMC_BLOCK_MINORS=32
 CONFIG_MMC_ARMMMCI=y