include math.h for log2(), pow(), and log10()

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@56638 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.in.ogr/main.c

@@ -21,6 +21,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <math.h>
 #include <grass/gis.h>
 #include <grass/dbmi.h>
 #include <grass/vector.h>