Fix several pointer-bool-conversion warnings that could cause cores

cde/programs/dtcreate/af_aux.c

@@ -220,7 +220,7 @@ void getAF_Icons(FiletypeData *pFiletypedata)
   /***************************************************************/
   pIconData = GetIconDataFromWid(AF_MED_IconGadget);
   if ( (pIconData->pmDirtyBit) &&
-       (pIconData->pmFileName) &&
+       (pIconData->pmFileName[0]) &&
        (strlen(pIconData->pmFileName)) ) {
      pFiletypedata->pszMedPmIcon = XtMalloc(strlen(pIconData->pmFileName) + 1);
      if (pFiletypedata->pszMedPmIcon) {
@@ -234,7 +234,7 @@ void getAF_Icons(FiletypeData *pFiletypedata)
   /* Medium Bitmap                                               */
   /***************************************************************/
   if ( (pIconData->bmDirtyBit) &&
-       (pIconData->bmFileName) &&
+       (pIconData->bmFileName[0]) &&
        (strlen(pIconData->bmFileName)) ) {
      pFiletypedata->pszMedBmIcon = XtMalloc(strlen(pIconData->bmFileName) + 1);
      if (pFiletypedata->pszMedBmIcon) {
@@ -249,7 +249,7 @@ void getAF_Icons(FiletypeData *pFiletypedata)
   /***************************************************************/
   pIconData = GetIconDataFromWid(AF_TINY_IconGadget);
   if ( (pIconData->pmDirtyBit) &&
-       (pIconData->pmFileName) &&
+       (pIconData->pmFileName[0]) &&
        (strlen(pIconData->pmFileName)) ) {
      pFiletypedata->pszTinyPmIcon = XtMalloc(strlen(pIconData->pmFileName) + 1);
      if (pFiletypedata->pszTinyPmIcon) {

cde/programs/dtcreate/cmnrtns.c

@@ -700,7 +700,7 @@ void SetIconData(Widget wid, char *pszIconFile, enum icon_size_range enumIconSiz
   pIconData = GetIconDataFromWid(wid);
   if (pIconData) {
      if ( (pIconData->pmDirtyBit) &&
-          (pIconData->pmFileName) &&
+          (pIconData->pmFileName[0]) &&
           (strlen(pIconData->pmFileName)) ) {
 #ifdef DEBUG
         printf("SetIconData: unlink '%s'\n", pIconData->pmFileName);  /* debug */

cde/programs/dtcreate/main.c

@@ -634,7 +634,7 @@ void RemoveTmpIconFiles( void )
 
   for (i=0; i < ICON_NUMBER; i++) {
      if ( (IconDataList[i]->pmDirtyBit) &&
-          (IconDataList[i]->pmFileName) &&
+          (IconDataList[i]->pmFileName[0]) &&
           (strlen(IconDataList[i]->pmFileName)) ) {
 #ifdef DEBUG
         printf("RemoveTmpIconFiles: unlink '%s'\n", IconDataList[i]->pmFileName);  /* debug */