bus: mhi: host: pci_generic: Add support for SA8775P endpoint

bus: mhi: host: pci_generic: Add support for SA8775P endpoint

Add MHI controller config for SA8775P endpoint. SA8775P supports IP_SW
usecase only. Hence use separate configuration to enable IP_SW channels.

Signed-off-by: Mrinmay Sarkar <quic_msarkar@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20241205065422.2515086-2-quic_msarkar@quicinc.com
[mani: updated commit message and removed 'modem' reference in config]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>