[MTD] [NAND] fsl_upm: fix build problem with 2.6.28-rc2

The patch fixes following build error:

  CC      drivers/mtd/nand/fsl_upm.o
drivers/mtd/nand/fsl_upm.c: In function 'fun_chip_init':
drivers/mtd/nand/fsl_upm.c:168: warning: passing argument 2 of 'of_mtd_parse_partitions' from incompatible pointer type
drivers/mtd/nand/fsl_upm.c:168: warning: passing argument 3 of 'of_mtd_parse_partitions' from incompatible pointer type
drivers/mtd/nand/fsl_upm.c:168: error: too many arguments to function 'of_mtd_parse_partitions'
make[1]: *** [drivers/mtd/nand/fsl_upm.o] Error 1

The breakage was introduced in 69fd3a8d
("[MTD] remove unused mtd parameter in of_mtd_parse_partitions()").

While at it, also add a check for the of_mtd_parse_partitions() return
value.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>