rtw88: 8822c: support FW crash dump when FW crash

Although FW crash logs are already supported for dumping in driver, the
logs may not be sufficient to analyze field issues. To improve this part,
we add a support to dump FW memory.

When driver receives FW crash notifications, driver uses DDMA, which is a
HW ability, to copy specified FW memory to FW fifo. Driver can then dump
these information from FW fifo. With this support, not only FW crash log
but also specified FW memory will be dumped while FW crash. Besides,
specified registers are also dumped.

This feature is implemeted on 8822C first due to difference of FW layouts
between ICs. In addition, we add a debugfs to trigger FW crash. It can
simulate the process of crash, dump and reset. Through it, we can also
check if a reset is ongoing.

Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210309060121.9099-1-pkshih@realtek.com