test: Add proper prototypes for main() function

Warned-by: gcc

test/bzero.c

@@ -28,7 +28,7 @@
 #include <string.h>
 
 int
-main()
+main(int argc, char *argv[])
 {
 	unsigned char array[40];
 	size_t i;

test/closefrom.c

@@ -31,7 +31,7 @@
 #include <stdio.h>
 
 int
-main()
+main(int argc, char *argv[])
 {
 	int i;
 	int fd;

test/endian.c

@@ -30,7 +30,7 @@
 #include <string.h>
 
 int
-main()
+main(int argc, char *argv[])
 {
 	unsigned char decstream[] = {
 		0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,

test/fpurge.c

@@ -27,7 +27,7 @@
 #include <stdio.h>
 
 int
-main()
+main(int argc, char *argv[])
 {
 	static FILE fp_bad;
 	FILE *fp;

test/md5.c

@@ -37,7 +37,7 @@ test_md5(const char *digest, const char *string)
 }
 
 int
-main()
+main(int argc, char *argv[])
 {
 	test_md5("d41d8cd98f00b204e9800998ecf8427e", "");
 	test_md5("900150983cd24fb0d6963f7d28e17f72", "abc");

test/overlay.c

@@ -45,7 +45,7 @@
 #include <unistd.h>
 
 int
-main()
+main(int argc, char *argv[])
 {
 	/* Test that we do not get partial definitions. */
 	fflush(stdout);