i2c: s3c2410: Cleanup indentation and comment style

Improve the readability by:
 - fixing indentation,
 - switching to proper block comments,
 - removing spurious blank lines,
 - checkpatch: void function return statements are not generally useful,
 - checkpatch: braces {} are not necessary for any arm of this
   statement,
 - checkpatch: missing a blank line after declarations.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>