staging: brcm80211: moved typedefs to decrease header file dependencies

Code cleanup. Moved the typedefs to brcmsmac/types.h for source files that
only require opaque pointer definitions. Next patches will decrease the
number of #includes for each file.

Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Reviewed-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>