Staging: sm750fb: ddk750_swi2c.h: Replace spaces with tabs

Replace spaces with tabs at the start of lines in
ddk750_swi2c.h to rectify the following checkpatch warning:
WARNING: please, no spaces at the start of a line
Signed-off-by: Isaac Assegai <isaac.a.travers@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>