* lib/linux/riscv64-mes-gcc/_exit.c,
lib/linux/riscv64-mes-gcc/_write.c,
lib/linux/riscv64-mes-gcc/crt1.c,
lib/linux/riscv64-mes-gcc/syscall-internal.c,
lib/linux/riscv64-mes-gcc/syscall.c: New files to make it possible
to compile mes for riscv64-mes-gcc.
