bus: mhi: core: Improve mhi_sync_power_up handling for SYS_ERR state

Allow mhi_sync_power_up to handle SYS_ERR during power-up, reboot,
or recovery. This is to avoid premature exit when MHI_PM_IN_ERROR_STATE is
observed during above mentioned system states.

To achieve this, treat SYS_ERR as a valid state and let its handler process
the error and queue the next transition to Mission Mode instead of aborting
early.

Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
[mani: reworded description]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Link: https://patch.msgid.link/20250912-uevent_vdev_next-20250911-v4-5-fa2f6ccd301b@quicinc.com