cast5

aes: consolidate backend configuration under `aes_backend` (#541) #987

Job	Run time
test (stable)	18s
build (1.85.0, thumbv7em-none-eabi)	17s
build (stable, wasm32-unknown-unknown)	19s
build (1.85.0, wasm32-unknown-unknown)	18s
test (1.85.0)	27s
build (stable, thumbv7em-none-eabi)	16s
minimal-versions / minimal-versions	29s
	2m 24s

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