Add some function prototypes; NFC

(This file is compiled with -pedantic enabled in some two-stage builds)

Author: AaronBallman

clang/tools/c-index-test/c-index-test.c

@@ -66,7 +66,7 @@ extern char *dirname(char *);
 #endif
 
 /** Return the default parsing options. */
-static unsigned getDefaultParsingOptions() {
+static unsigned getDefaultParsingOptions(void) {
   unsigned options = CXTranslationUnit_DetailedPreprocessingRecord;
 
   if (getenv("CINDEXTEST_EDITING"))
@@ -3316,7 +3316,7 @@ typedef struct {
   unsigned num_files;
 } ImportedASTFilesData;
 
-static ImportedASTFilesData *importedASTs_create() {
+static ImportedASTFilesData *importedASTs_create(void) {
   ImportedASTFilesData *p;
   p = malloc(sizeof(ImportedASTFilesData));
   assert(p);
@@ -4407,7 +4407,7 @@ static void print_usr(CXString usr) {
   clang_disposeString(usr);
 }
 
-static void display_usrs() {
+static void display_usrs(void) {
   fprintf(stderr, "-print-usrs options:\n"
         " ObjCCategory <class name> <category name>\n"
         " ObjCClass <class name>\n"