LibC: Implement basic tzset()

I still don't have timezone support so this just sets values to UTC

userspace/libraries/LibC/time.cpp

@@ -9,6 +9,10 @@
 #include <time.h>
 #include <unistd.h>
 
+int daylight;
+long timezone;
+char* tzname[2];
+
 int clock_gettime(clockid_t clock_id, struct timespec* tp)
 {
 	return syscall(SYS_CLOCK_GETTIME, clock_id, tp);
@@ -196,6 +200,14 @@ struct tm* localtime(const time_t* timer)
 	return localtime_r(timer, &tm);
 }
 
+void tzset()
+{
+	daylight = 0;
+	timezone = 0;
+	tzname[0] = const_cast<char*>("UTC");
+	tzname[1] = const_cast<char*>("UTC");
+}
+
 size_t strftime(char* __restrict s, size_t maxsize, const char* __restrict format, const struct tm* __restrict timeptr)
 {
 	size_t len = 0;
@@ -544,13 +556,3 @@ size_t strftime(char* __restrict s, size_t maxsize, const char* __restrict forma
 	s[len++] = '\0';
 	return len;
 }
-
-
-
-#include <BAN/Assert.h>
-
-long timezone;
-void tzset()
-{
-	ASSERT_NOT_REACHED();
-}