wil6210: add support for reading multiple RFs temperature via debugfs

Base-band chips support multi RFs chips. Add support for reading
multiple RFs temperature via debugfs.

Signed-off-by: Tzahi Sabo <stzahi@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>