generator: Rework random number seeding to not use deprecated functions

g_get_current_time() is deprecated in the upcoming GLib release as it’s
not year-2038-safe. Use g_get_real_time() instead and slightly rework
the seeding to use the full range of numbers available.

Signed-off-by: Philip Withnall <withnall@endlessm.com>
1 job for deprecation-fixes in 6 minutes and 4 seconds (queued for 1 second)
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build-and-test

00:06:04