fix a compiler warning, void* versus void(*)(void)

src/include/inpptree.h

@@ -50,7 +50,7 @@ typedef struct INPparseNode {
     int valueIndex;         /* If INP_VAR, index into vars array. */
     char *funcname;         /* If INP_FUNCTION, name of function, */
     int funcnum;            /* ... one of PTF_*, */
-    void *function;         /* ... and pointer to the function. */
+    void (*function)(void); /* ... and pointer to the function. */
     void *data;                 /* private data for certain functions, currently PTF_PWL */
 } INPparseNode;
 

src/spicelib/parser/inpptree.c

@@ -42,7 +42,7 @@ extern IFsimulator *ft_sim;	/* XXX */
 static struct op {
     int number;
     char *name;
-    void *funcptr;
+    void (*funcptr)(void);
 } ops[] = {
     {
     PT_COMMA,  ",", NULL}, {
@@ -58,7 +58,7 @@ static struct op {
 static struct func {
     char *name;
     int number;
-    void *funcptr;
+    void (*funcptr)(void);
 } funcs[] = {
     { "abs",    PTF_ABS,    (void(*)(void)) PTabs } ,
     { "acos",   PTF_ACOS,   (void(*)(void)) PTacos } ,