EMI Filter calculation in a SMPS
The value of inductance is typical for a line filter and is non crucial.
 The purpose of the filter is to isolate  SMPS HF components from the mains.
 The inductors form two mirror image coupled Pi-filters (split along the middle horizontal axis for analysis. 

Line filters can be common mode - which reject noise on the line relative to ground as if the line was a single conductor
 or differential mode, which block signals from being injected into the mains and adding to the mains signal which is itself differential mode. 

A properly implemented filter will often have both differential and common mode filters.
 As shown the current design has neither :-(.

I strongly suspect that the diagram has been dawn wrongly - it does not match the diagram in the second version of the data sheet that I added into the question. The 2nd datasheet shows a "Z" symbol on the filter inductor which I take to mean that the dotted ends are on opposing ends of the coil. (See digram below to make sense of this.) The blue "Z" was present but I have coloured it blue. I have added the red ellipse and the dotting which I think is implied. 

 

In a common mode filter the "dotting" on each winding will be on the same "side" of the filter - either both on the line side or both on the equipment side. To function properly the filter needs to be followed by a ground referenced capacitor so the cap needs to be split into two caps with a griunded centre tap. See left hand part of diagram below.

A differential mode filter has dottings on opposite side of the filter and the associated capacitor need not be centre tapped and grounded. See right hand part of diagram below. 

The filter as shown in the supplied circuit has common mode dotting but differential mode capacitor connections - ie no centre tapped caps.
 It will work far less well than it would if Cin1 was two caps in series with the centre grounded OR if two more caps were added in series across Cin1 with their centre point grounded. Image from here.



A internet search for "line filter" will turn up many examples.

Related material - each linked to a page. 

FSGM data sheet as a JPG !