Remove switch in sxw_resource.c

[chaukap]

On line 270 there is a switch statement that used to assign different transpiration fractions to different rgroups.

        switch (t) {
            case 0://Tree
                transp = SXW.transpTotal;
                break;
            case 1://Shrub
                transp = SXW.transpTotal;
                break;
            case 2://Grass
                transp = SXW.transpTotal;
                break;
            case 3://Forb
                transp = SXW.transpTotal;
                break;
            default:
                transp = SXW.transpTotal;
                break;
            }

Since we are using space now all of the switch cases do the exact same thing. Therefore, the entire switch can be replaced with

transp = SXW.transpTotal;

[kpalmqui]

@chaukap good idea, thanks!