msm: vidc: Increase fw unload delay to 20 secs

If you start recording a video and suddenly put the device into sleep (without stopping the recording), the vidc firmware unloads too quickly, resulting in these errors:
[   77.515800] msm_vidc: 1: Wait interrupted or timeout for PC_PREP_DONE: 0
[   77.515835] msm_vidc: 1: Failed to prepare for PC -5
[   77.516223] msm_vidc: 1: venus_hfi_iface_cmdq_write_nolock - fw not in init state
[   77.516253] msm_vidc: 1: Failed to set OCMEM on driver
[   77.516279] msm_vidc: 1: Failed to set ocmem: -39

Increasing the vidc firmware unload delay to 20 secs gives vidc enough time to complete power-collapse, thus fixing these errors.

Signed-off-by: Sultanxda <sultanxda@gmail.com>