Fix: Add proper function prototype for ZHEMM BLAS function

Replace the bare extern declaration with a proper function prototype that
specifies all 12 parameters. This resolves the "too many arguments to function"
compilation error by providing the compiler with the correct function signature.

Fixes the build failure in herm_matrix_mult.c:22

Author: jrfaeder

bng2/Network3/src/util/mathutils/herm_matrix_mult.c

@@ -13,7 +13,7 @@ void HERM_MATRIX_MULT(dcomplex **a, dcomplex **b, dcomplex **c, int dim){
     int n=dim;
     dcomplex alpha={1.0,0.0};
     dcomplex beta={0.0,0.0};
-    extern void ZHEMM();
+    extern void ZHEMM(char*, char*, int*, int*, dcomplex*, dcomplex*, int*, dcomplex*, int*, dcomplex*, dcomplex*, int*);
 
     /* transpose necessary because of opposite way Fortran references */
     /* arrays */