wifi: rtw89: debugfs: support multiple adapters debugging

wifi: rtw89: debugfs: support multiple adapters debugging

The rtw89 uses debugfs to access registers and driver states. To get
a range of registers, the range value is set and stored to a variable, and
get the set of register values by the stored range. However, the variable
is a static global variable, which multiple adapters will be a problem,
so move the variable to adapter context rtw89_dev.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240816115700.17390-1-pkshih@realtek.com