19078: cpu/esp32: define FLASHFILE_POS r=benpicco a=gschorcht
### Contribution description
Instead of using a fixed position of the image file in the flash, the variable `FLASHFILE_POS` is used which allows to override the default position of the image in the flash at 0x10000.
This PR is a prerequisite for the `periph_flashpage` implementation PR #19079.
### Testing procedure
Flashing a ESP32x SoC should work with `FLASHFILE_POS=0x20000`, for example:
```
USEMODULE=esp_log_startup FLASHFILE_POS=0x20000 BOARD=esp32-wroom-32 make -j8 -C tests/shell flash
```
The bootloader output should give `00020000` as offset for the `factory` partition
```
I (75) boot: Partition Table:
I (78) boot: ## Label Usage Type ST Offset Length
I (84) boot: 0 nvs WiFi data 01 02 00009000 00006000
I (91) boot: 1 phy_init RF data 01 01 0000f000 00001000
I (97) boot: 2 factory factory app 00 00 00020000 000199b0
I (104) boot: End of partition table
```
and
```
I (125) esp_image: segment 0: paddr=00020020 vaddr=3f400020 size=02140h ( 8512) map
```
during the load of the image.
### Issues/PRs references
Prerequisite for PR #19079
Co-authored-by: Gunar Schorcht <gunar@schorcht.net>
Using `sectoins.ld.in` instead of a static `sections.ld`, from which the actual used `sections.ld` is generated with the C preprocessor, allows to use the configuration in `sdkconfig.h` as well as Kconfig to use a custom section layout.
Using the vendor `memory.ld.in` instead of a static `memory.ld`, from which the actual used `memory.ld` is generated with the C preprocessor, allows to use the configuration in `sdkconfig.h` as well as Kconfig to use a custom memory layout. For example, it is no longer necessary to maintain different `memory.ld` files for the ESP32 BLE module, since the memory layout is now defined from the values of the configuration.
Instead of using a fixed position of the image file in the flash, the variable `FLASHFILE_POS` is used which allows to override the default position of the image in the flash at 0x10000.
The `usbdev_synopsys_dwc2 driver` requires the `ztimer_msec` module and is therefore responsible for pulling it in. Therefore, the dependency on `ztimer_msec` can be removed here.
The definition in `pkg/esp32_sdk/Makefile.include` was evaluated by
`make` after the include paths were already set, resulting in
`ESP32_SDK_DIR` being empty in
INCLUDES += -I$(ESP32_SDK_DIR)/components
[...]
This in turn resulted in
cc1: error: /components: No such file or directory [-Werror=missing-include-dirs]
[...]
This file is an excerpt of STM32 header file `stm32/smsis/f7/include/stm32f767xx.h` since the ESP32x SoCs use the same Synopsys DWC2 IP core as USB peripherals.
Since `esp_can.h` is included by main `cpu/esp32/include/periph_cpu.h` after the include of the specific `periph_cpu_$(CPU_FAM)`, it is not necessary to include `esp_can.h` in each specific `periph_cpu_$(CPU_FAM)`.
With the improvements of the locking mechanism, thread safety of malloc/realloc/calloc/free is guaranteed. Module malloc_thread_safe is not needed any longer.
