rtlwifi: btcoexist: remove undefined Kconfig macros

There are references to four undefined Kconfig macros in the code.
Commit 8542373d

 ("Staging: rtl8812ae: remove undefined Kconfig
macros") removed identical references from that staging driver, but
they resurfaced in rtlwifi. Remove these again as the checks for them
still will always evaluate to false.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>