ttyFDC: Fix build problems due to use of module_{init,exit}

ttyFDC: Fix build problems due to use of module_{init,exit}

Commit 0fd972a7d91d (module: relocate module_init from init.h to
module.h) broke the build of ttyFDC driver due to that driver's (mis)use
of module_mips_cdmm_driver() without first including module.h, for
example:

In file included from ./arch/mips/include/asm/cdmm.h +11 :0,
                 from drivers/tty/mips_ejtag_fdc.c +34 :
include/linux/device.h +1295 :1: warning: data definition has no type or storage class
./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’
include/linux/device.h +1295 :1: error: type defaults to ‘int’ in declaration of ‘module_init’ [-Werror=implicit-int]
./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: warning: parameter names (without types) in function declaration

Instead of just adding the module.h include, switch to using the new
builtin_mips_cdmm_driver() helper macro and drop the remove callback,
since it isn't needed. If module support is added later, the code can
always be resurrected.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.2.x-
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>