support ark_bn254 instead of the blstrs curve

[montekki]

No description provided.

[montekki]

upstream crate on blstrs:

running 1 test
Testing Multiexp for 1048576 elements...
GPU took 187ms.
CPU took 10461ms.
Speedup: x55.941177
============================
Testing Multiexp for 2097152 elements...
GPU took 330ms.
test gpu_multiexp_consistency has been running for over 60 seconds
CPU took 19623ms.
Speedup: x59.463634
============================
Testing Multiexp for 4194304 elements...
GPU took 610ms.
CPU took 38016ms.
Speedup: x62.321312
============================
Testing Multiexp for 8388608 elements...
GPU took 1086ms.
CPU took 74502ms.
Speedup: x68.60221
============================
Testing Multiexp for 16777216 elements...
GPU took 2041ms.
CPU took 147639ms.
Speedup: x72.3366
============================
Testing Multiexp for 33554432 elements...
GPU took 3985ms.
CPU took 305801ms.
Speedup: x76.738014
============================
test gpu_multiexp_consistency ... ok

this PR:

Testing Multiexp for 1048576 elements...
GPU took 730ms.
CPU took 44117ms.
Speedup: x60.434246
============================
Testing Multiexp for 2097152 elements...
GPU took 1363ms.
CPU took 83118ms.
Speedup: x60.98166
============================
Testing Multiexp for 4194304 elements...
GPU took 2644ms.
CPU took 156407ms.
Speedup: x59.155445
============================
Testing Multiexp for 8388608 elements...
GPU took 5204ms.
CPU took 314931ms.
Speedup: x60.5171
============================
Testing Multiexp for 16777216 elements...
GPU took 10225ms.
CPU took 616370ms.
Speedup: x60.280685
============================
Testing Multiexp for 33554432 elements...
GPU took 20311ms.
CPU took 1173890ms.
Speedup: x57.795776
============================
test gpu_multiexp_consistency ... ok