Support long C_x #1135

Job	Run time
check-style	15s
generate-fstar	2m 19s
test-lakers-python	53s
unit-tests (lakers-crypto/psa, ead-none)	50s
unit-tests-default	53s
unit-tests (lakers-crypto/psa, ead-authz)	51s
unit-tests (lakers-crypto/rustcrypto, ead-none)	43s
unit-tests (lakers-crypto/rustcrypto, ead-authz)	44s
build-coap-example	53s
build-edhoc-package (lakers-crypto/psa)	1m 21s
build-example-for-cortex-m4 (crypto-psa)	1m 32s
build-lakers-c (crypto-rustcrypto)	1m 3s
build-edhoc-package (lakers-crypto/psa-baremetal)	2m 5s
build-example-for-cortex-m4 (crypto-cryptocell310)	1m 7s
build-edhoc-package (lakers-crypto/cryptocell310)	1m 8s
build-lakers-c (crypto-psa-baremetal)	1m 16s
build-lakers-c-example	1m 59s
build-lakers-c (crypto-cryptocell310)	1m 17s
build-edhoc-package (lakers-crypto/rustcrypto)	57s
run-example-on-qemu (crypto-psa)	1m 49s
release	0s
	23m 55s

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