embedded-hal-nb updates

[eldruin]

A couple small updates

[rust-highfive]

r? @ryankurte

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[bors[bot]]

Build succeeded:

• fmt
• test (1.54.0, thumbv6m-none-eabi)
• test (1.54.0, thumbv7m-none-eabi)
• test (1.54.0, x86_64-unknown-linux-gnu)
• test (nightly, thumbv6m-none-eabi)
• test (nightly, thumbv7m-none-eabi)
• test (nightly, x86_64-unknown-linux-gnu)
• test (stable, thumbv6m-none-eabi)
• test (stable, thumbv7m-none-eabi)
• test (stable, x86_64-unknown-linux-gnu)