base-files: use hwclock --systz

The date -k patch is non standard and will be removed in the next
commit.

Tested behavior to be identical with a simple C program:

 #define _GNU_SOURCE
 #include <unistd.h>
 #include <stdio.h>
 #include <sys/time.h>
 #include <sys/syscall.h>

int main()
{
        struct timezone tt;
	struct timezone tz;

        int a = syscall(SYS_gettimeofday, NULL, &tt);
        int b = gettimeofday(NULL, &tz);
        printf("%d - %d, %d\n", a, tt.tz_minuteswest, tt.tz_dsttime);
        printf("%d - %d, %d\n", b, tz.tz_minuteswest, tz.tz_dsttime);
}

Signed-off-by: Rosen Penev <rosenp@gmail.com>

package/base-files/files/etc/init.d/system

@@ -27,7 +27,7 @@ system_config() {
 		ln -sf "/usr/share/zoneinfo/$zonename" /tmp/localtime && rm -f /tmp/TZ
 
 	# apply timezone to kernel
-	busybox date -k
+	hwclock -u --systz
 }
 
 reload_service() {