serial: uartlite: Fix compilation issue on !OF platforms

serial: uartlite: Fix compilation issue on !OF platforms

There is missing ulite_of_match on !OF platforms.
Use of_match_ptr() to fix it.

Warning log:
drivers/tty/serial/uartlite.c: In function ‘ulite_get_id’:
drivers/tty/serial/uartlite.c:774:33: error: ‘ulite_of_match’ undeclared
(first use in this function)
   ret = of_alias_get_alias_list(ulite_of_match, "serial",
                                 ^
drivers/tty/serial/uartlite.c:774:33: note: each undeclared identifier
is reported only once for each function it appears in

Signed-off-by: Michal Simek <michal.simek@xilinx.com>