Fixes particle species name issue in EM2D
Fixes particle species name issue in EM2D

* The size of the particle name buffer did not respect the MAX_SPNAME_LEN macro, this fixes it.

Signed-off-by: Ricardo Fonseca <2b0ac934d3c4bb6f7423a3f8fc4e37020d0ec923@tecnico.ulisboa.pt>

zambzamb/zpic,zambzamb/zpic,zambzamb/zpic