staging: brcm80211: deleted inactive BCMDBG_FORCEHT code

Code cleanup. Preprocessor flag BCMDBG_FORCEHT is never defined,
is a debug feature, so ifdeff'ed code has been removed. The removed
section would force the backplane clock on HT rate, which
facilitates debug but has a negative effect on power usage.

Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>