When libc.so.6 is not present on the system, lv_timer triggers an OSError exception or even a hard crash (segfault). This dependency is unnecessarily specific, because alternative implementations of libc (such as uClibc-ng) are also compatible.
micropython-lib/unix-ffi provides a nice way to load the library, but I am not sure if this module is always available to the bindings. In any case, the code (in driver\linux\lv_timer.py) would look like this:
import ffilib
# FFI libraries
libc = ffilib.libc()
try:
librt = ffilib.open("librt")
except OSError as e:
librt = libc