Staging: sm750fb: Fix spelling error in TODO

Fixed spelling error in TODO.
Signed-off-by: Robin Karlsson <s.r.karlsson@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/sm750fb/TODO

 TODO:
-- lots of clechpatch cleanup
+- lots of checkpatch cleanup
 - use kernel coding style
 - refine the code and remove unused code
 - check on hardware effects of removal of USE_HW_I2C and USE_DVICHIP (these two