Package load time is quite long, and longer on Julia 1.10

[jgreener64]

This isn't the end of the world, but something worth keeping an eye on. This is with Enzyme main (443f798), Ubuntu and 18 threads.

@time using Enzyme

With Julia 1.7.2:

  9.343872 seconds (15.13 M allocations: 836.380 MiB, 6.14% gc time, 93.39% compilation time)

With Julia 1.8.5:

 15.986613 seconds (31.91 M allocations: 1.708 GiB, 6.90% gc time, 91.74% compilation time: 33% of which was recompilation)

With Julia 1.9.2:

  7.214598 seconds (14.60 M allocations: 988.510 MiB, 7.17% gc time, 91.72% compilation time)

With Julia 1.10.0:

 13.227393 seconds (17.16 M allocations: 1.194 GiB, 3.57% gc time, 97.53% compilation time)

[wsmoses]

Going to mark as a duplicate of #506 and #776

However, the issue presently is partially that the Julia compiler itself is not well tuned to handle the cfunction registration iirc.

cc @vchuravy @KristofferC