wifi: rtw88: Fix sparse warning for rtw8822b_hw_spec

Sparse lists the following for rtw88:

  CHECK   drivers/net/wireless/realtek/rtw88/rtw8822b.c
drivers/net/wireless/realtek/rtw88/rtw8822b.c:2500:22: warning: symbol 'rtw8822b_hw_spec' was not declared. Should it be static?

The warning arises because the external declaration for rtw8822b_hw_spec
occurs in rtw8822be.h, which is not included in rtw8822b.h. That line is
moved, and the now empty file rtw8822be.h is deleted.

Symbol 'rtw8822b_hw_spec' can be made constant.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220524153621.19027-2-Larry.Finger@lwfinger.net