staging: brcm80211: brcmfmac: remove unnecessary cflags, WL_ISCAN_DISABLED & WL_ROAM_DISABLED

Remove unnecessary cflags, WL_ISCAN_DISABLED
and WL_ROAM_DISABLED. Iscan is ON and Roam by FW
is OFF by default.

Signed-off-by: Nohee Ko <noheek@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>