Fix errors when compiling on newer compilers (prototype definitions fix)

src/credits.c

@@ -6,7 +6,7 @@
 #define THE_PLUSH "Ploosh"
 
 #define T void
-#define R print_credits() {
+#define R print_credits(void) {
 #define O fprintf
 #define U (
 #define B stdout

src/devhelper.c

@@ -93,7 +93,7 @@ int subscribe_cmd(usbmuxd_event_cb_t device_event_cb, irecv_device_event_cb_t ir
 	return 0;
 }
 
-int unsubscribe_cmd()
+int unsubscribe_cmd(void)
 {
 	usbmuxd_events_unsubscribe(usbmuxdctx);
 	irecv_device_event_unsubscribe(irecvctx);

src/exec_checkra1n.c

@@ -30,7 +30,7 @@ char* ext_checkra1n = NULL;
 
 #define tmpdir getenv("TMPDIR") == NULL ? "/tmp" : getenv("TMPDIR")
 
-int exec_checkra1n() {
+int exec_checkra1n(void) {
 	LOG(LOG_INFO, "About to execute checkra1n");
 	int fd, ret;
 	char* checkra1n_path = NULL;

src/lock_vars.c

@@ -55,7 +55,7 @@ static bool set_locked_bool(bool* val, bool newval, pthread_mutex_t* mutex) {
     return newval;
 }
 
-bool get_spin() {
+bool get_spin(void) {
     return get_locked_bool(&spin, &spin_mutex);
 }
 
@@ -63,7 +63,7 @@ bool set_spin(bool newval) {
     return set_locked_bool(&spin, newval, &spin_mutex);
 }
 
-bool get_found_pongo() {
+bool get_found_pongo(void) {
    return get_locked_bool(&found_pongo, &found_pongo_mutex);
 }
 
@@ -71,7 +71,7 @@ bool set_found_pongo(bool val) {
     return set_locked_bool(&found_pongo, val, &found_pongo_mutex);
 }
 
-uint64_t get_ecid_wait_for_dfu() {
+uint64_t get_ecid_wait_for_dfu(void) {
     LOG(LOG_VERBOSE5, "locking ecid wait for dfu mutex for get");
     pthread_mutex_lock(&ecid_dfu_wait_mutex);
     uint64_t ret = ecid_wait_for_dfu;

src/main.c

@@ -16,7 +16,6 @@
 #include <signal.h>
 #include <pthread.h>
 #include <inttypes.h>
-#include <getopt.h>
 #include <errno.h>
 #include <spawn.h>
 #include <sys/mman.h>
@@ -56,7 +55,7 @@ void thr_cleanup(void* ptr) {
 	*(int*)ptr = 0;
 }
 
-int build_checks() {
+int build_checks(void) {
 #if defined(__APPLE__)
 #ifndef NO_CHECKRAIN
 	struct mach_header_64* c1_header = (struct mach_header_64*)&checkra1n[0];