There would be three lines. The south bound line to VSP and the two lines to MAS and HWH. Even though the bifurcation point is about 10km out from WAT station, the operations for that point were still managed by WAT station, so WAT would be termed as a junction. To speak in more modern terms, the bifurcation point would be under the signalling territory of WAT station, so WAT would be termed as the junction point.
And note that at the time all these railway connections came up, there were no stations near the junction point. WAT was pretty much the only station handling all the points and the bifurcation point was put far out only...
more...

because of the geographical constraints. So, it was pretty much a junction.

A link for reference:
click here : This is a record of all railway operations in the country from 1908-09. You can see that in the Madras railway section, it mentions the station at Waltair as a junction station and the branch to VSP as the branch line taking off from the junction station.
The entry for Bengal Nagpur railway (114) also refers to it as Waltair junction only.
...
more...

That said, the practice of naming stations as a junction is somewhat shaky. For example, WJR (Walajah Road) in SR used to be a junction for a long time with a branch line to Ranipet. Now that line is defunct and the station board too does not have the 'Jn' in it, but the station name is still listed as Walajah Road junction as in IR's official site. VSKP has a similar situation.