fs Add mount subcommand

ulib/system/system.c

@@ -43,3 +43,11 @@ int32_t devctl(Dev_t *devh, uint64_t cmd, uint8_t *buffer, size_t len, uint64_t
 int32_t rand(void) {
   return syscall(SYS_RAND, 0, 0, 0, 0, 0, 0);
 }
+
+int32_t vfsmount(char *mountpoint, char *fstype, Dev_t *dev, bool format) {
+  return syscall(SYS_VFSMOUNT, (uint64_t)mountpoint, (uint64_t)fstype, (uint64_t)dev, (uint64_t)format, 0, 0);
+}
+
+int32_t vfsunmount(char *mountpoint) {
+  return syscall(SYS_VFSUNMOUNT, (uint64_t)mountpoint, 0, 0, 0, 0, 0);
+}