fs-tests: test_1: fix compilation warnings

fs-tests: test_1: fix compilation warnings

Fix the following compilation warnings:
test_1.c: In function ‘test_1’:
test_1.c:67:4: warning: format ‘%llu’ expects type ‘long long unsigned int’, but argument 3 has type ‘uint64_t’
test_1.c:88:3: warning: format ‘%llu’ expects type ‘long long unsigned int’, but argument 3 has type ‘uint64_t’

The fix is to cast the argument with (unsigned long long).

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>