fix(esp8266): Use custom flash config due to different ROM implementation

[Dzarda7]

ESP8266 contains g_rom_flashchip, but it is in different order than esp_rom_spiflash_chip_t, esp_rom_spiflash_config_param might take also different order of parameters but due to missing possibility to check in ROM code custom implementation seems like okay solution preventing possible future issues.

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[Copilot]

Pull request overview

Adjusts ESP8266 flash configuration handling to avoid relying on ROM structs/functions whose field/parameter ordering may not match esp_rom_spiflash_chip_t.

Changes:

• Replaces the ESP8266 ROM g_rom_flashchip usage with a custom in-RAM esp_rom_spiflash_chip_t instance.
• Adds an ESP8266-specific stub_target_flash_update_config() implementation that updates the custom struct.
• Marks the common stub_target_flash_update_config() as weak so targets can override it.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
src/target/esp8266/src/flash.c	Introduces a custom flashchip config struct and overrides config update/getter for ESP8266.
src/target/common/src/flash.c	Makes the default stub_target_flash_update_config() weak to allow per-target overrides.

[erhankur]

Thanks for the fix. Is this because I removed macros and forced client codes to get flash params from config?

[Dzarda7]

Is this because I removed macros and forced client codes to get flash params from config?

Yes, I then had to use stub_lib_flash_get_config for some alignment on sector size which aligned it probably to block size (or some other field).

[Dzarda7]

FYI @radimkarnis