spi/s3c64xx: fix checkpatch warnings and error

Fix checkpatch warnings and error as below:
  ERROR: "foo * bar" should be "foo *bar"
  WARNING: please, no space before tabs
  WARNING: quoted string split across lines
  WARNING: msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>