[MIPS] DBAu1200: fix bad SMC 91C111 resource size

The on-board SMC 91C111 chip only decodes 16 bytes of memory (obviously, it
can not decode a whole megabyte starting from address 0x19000300).

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>