Added gatemate vendor and Updated init file #3424

Job	Run time
check-links	43s
document	48s
smoke (amaranth-lang/amaranth-boards)	33s
test (3.8)	2m 17s
smoke (amaranth-lang/amaranth-stdio)	42s
test (3.9)	2m 12s
smoke (amaranth-lang/amaranth-soc)	43s
test (3.10)	2m 8s
test (3.11)	2m 39s
test (3.12)	3m 18s
test (pypy-3.8)	5m 27s
test (pypy-3.9)	4m 45s
test (pypy-3.10)	4m 52s
test (3.13-dev)	2m 59s
publish-docs	17s
publish-docs-dev	0s
required	1s
publish-package	28s
publish-schemas	5s
publish-release	0s
	34m 57s

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