change the default tile size in prep_flt_init.m

[liu-ran]

Hi, the code "prep_flt_init.m" set the tile size as 3030. But my llc540 simulation use the tile of 6060. So I should replace all "30" with "60" in the "prep_flt_init.m" to repare my initial flt files, am I right? Many thanks!