ASoC: SOF: Intel: don't download firmware at each resume

Merge series from Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>:

After the first firmware boot, the firmware is capable of
saving/restoring its context to/from IMR (Isolated Memory Region, set
aside by BIOS on startup). This capability improves the resume speed.

Due to an unexplained issue on Up2 boards, this capability is disabled
on ApolloLake.

For backwards compatibility, the regular boot flow is used with older
firmware. For added peace of mind, a kernel module parameter is
provided to force the regular boot flow - this shouldn't be necessary
since we've been testing these patches for 6+ months.