minijail: refresh lib{syscalls|constants}gen.c for linux-x86 host
Crosvm with sandbox on x86 host as of Feb. 28 2020 fails with this error:
libminijail[43171]: compile_file: /usr/.../.../block_device.policy(19): nonexistent syscall 'statx'
block_device.policy whitelisting statx, where the libsyscalls.gen.c is missing it
Likely the two lib*.gen.c files were created a while ago when glibc version was low. Needs refresh.
Bug: 150394301
Test: Run cuttlefish enabling crosvm sandboxing with the rebuilt libminijail.so, and saw no error
Change-Id: I4f9ebecf1301571d53d127a5cb6eb40b7230b522
