Using floating point causes architecture dependent results due to accuracy/rounding differences. It is not hard to switch to fixed point, and while this does cause quite different rounding errors, the difference is small. Fixes: #200
Initially only the vfs5011 driver is tested. Please note that these tests will be unreliable before umockdev 0.13.2. See also https://github.com/martinpitt/umockdev/pull/92