Update stm32f4xx-hal requirement from 0.7.0 to 0.8.3

[dependabot-preview]

Updates the requirements on stm32f4xx-hal to permit the latest version.

Changelog

Sourced from stm32f4xx-hal's changelog.

[v0.8.3] - 2020-06-12

Fixed

• Make sure that I2C writes are concluded with a STOP condition

[v0.8.2] - 2020-05-29

Added

• Added sdio driver
• Allow specifying the desired SDIO bus speed during initialization

[v0.8.1] - 2020-05-10

Added

• Implement timer::Cancel trait for Timer<TIM>.
• Added DWT cycle counter based delay and stopwatch, including an example.

[v0.8.0] - 2020-04-30

Changed

• [breaking-change] Updated stm32f4 dependency to v0.11.
• Wait 16 cycles after setting prescalers for some clock domains to follow manual.
• Fixed TIM9 pclk and ppre.

Added

• Implement timer::Cancel trait for Timer<SYST>.
• Added PWM support and example.

[v0.7.0] - 2020-03-07

Changed

• Added more type states for open drain AF modes so we can prevent (potential fatal) I2C misuse
• [breaking-change] Updated stm32f4 dependency to v0.10.0.

Added

• Added examples in the examples folder.
• Added USB driver.
• PLL48Clk configuration.
• Added bit-banding implementation.
• Added support for RNG peripheral and rand_core, and an example that uses it.

[v0.6.0] - 2019-10-19

... (truncated)

Commits

• 6972554 Release 0.8.3
• c61beeb Merge pull request #169 from stm32-rs/stop-after-i2c-write
• 4c93814 Add CHANGELOG entry for I2C fix
• f12e781 Move I2C write implementation into write_bytes function
• 6ec8632 Merge pull request #168 from stm32-rs/0-8-2-release
• e91878b Prepare 0.8.2 release
• 7b619fa Merge #164
• 62aa647 Move sdio to unreleased section
• 5dcbbdf Merge #163
• 401a344 Add CHANGELOG entry for SDIO changes
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #35.