Fix AIX build

Fix AIX build failure with IBM xlC compiler due to conflicting
definition of M_PI.  The libSYS/include/genericStds.h definition is
guarded with #ifndef M_PI, but was included before <math.h> which
defines M_PI with more significant digits.

libSYS/src/genericStds.cpp

@@ -92,10 +92,10 @@ amm-info@iis.fraunhofer.de
 
 #define _CRT_SECURE_NO_WARNINGS
 
-#include "genericStds.h"
-
 #include <math.h>
 
+#include "genericStds.h"
+
 /* library info */
 #define SYS_LIB_VL0 1
 #define SYS_LIB_VL1 3