Include <linux/module.h> to fix below build error:

  CC      sound/soc/samsung/s3c-i2s-v2.o
sound/soc/samsung/s3c-i2s-v2.c:573: warning: data definition has no type or storage class
sound/soc/samsung/s3c-i2s-v2.c:573: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
sound/soc/samsung/s3c-i2s-v2.c:573: warning: parameter names (without types) in function declaration
sound/soc/samsung/s3c-i2s-v2.c:638: warning: data definition has no type or storage class
sound/soc/samsung/s3c-i2s-v2.c:638: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
sound/soc/samsung/s3c-i2s-v2.c:638: warning: parameter names (without types) in function declaration
sound/soc/samsung/s3c-i2s-v2.c:677: warning: data definition has no type or storage class
sound/soc/samsung/s3c-i2s-v2.c:677: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
sound/soc/samsung/s3c-i2s-v2.c:677: warning: parameter names (without types) in function declaration
sound/soc/samsung/s3c-i2s-v2.c: In function 's3c_i2sv2_register_dai':
sound/soc/samsung/s3c-i2s-v2.c:736: warning: initialization discards qualifiers from pointer target type
sound/soc/samsung/s3c-i2s-v2.c: At top level:
sound/soc/samsung/s3c-i2s-v2.c:754: warning: data definition has no type or storage class
sound/soc/samsung/s3c-i2s-v2.c:754: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
sound/soc/samsung/s3c-i2s-v2.c:754: warning: parameter names (without types) in function declaration
sound/soc/samsung/s3c-i2s-v2.c:756: error: expected declaration specifiers or '...' before string constant
sound/soc/samsung/s3c-i2s-v2.c:756: warning: data definition has no type or storage class
sound/soc/samsung/s3c-i2s-v2.c:756: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
sound/soc/samsung/s3c-i2s-v2.c:756: warning: function declaration isn't a prototype
make[3]: *** [sound/soc/samsung/s3c-i2s-v2.o] Error 1
make[2]: *** [sound/soc/samsung] Error 2
make[1]: *** [sound/soc] Error 2
make: *** [sound] Error 2
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>