tests: drivers: flash testing stm32 flash size

Add a special testcase to test any stm32 target
The expected flash size is given by the config FLASH_SIZE (in bytes)
and stm32 flash driver API function should return the same value
Do not run on the stm32wb55 nucleo as 216K are reserved among the 1MB
(only 808K declared but mcu has 1MB)

Signed-off-by: Francois Ramu <francois.ramu@st.com>

tests/drivers/flash/common/Kconfig

@@ -4,11 +4,15 @@
 # Device/scenario dependent information that is not available in
 # other ways.
 
+DT_CHOSEN_Z_FLASH := zephyr,flash
+
 config TEST_DRIVER_FLASH_SIZE
 	int "Size of flash device under test"
+	default $(dt_chosen_reg_size_int,$(DT_CHOSEN_Z_FLASH),0) if SOC_FAMILY_STM32
 	default -1
 	help
 	  Expected flash device size the test will validate against. If the flash driver does not
 	  support the get_size() API, leave this set as -1 to skip the test.
+	  For the STM32 devices, the flash size is direclty given by the soc DTSI.
 
 source "Kconfig.zephyr"

tests/drivers/flash/common/testcase.yaml

@@ -117,6 +117,14 @@ tests:
     extra_configs:
       - CONFIG_DMA=y
       - CONFIG_SOC_FLASH_SILABS_S2_DMA_READ=y
+  drivers.flash.common.stm32:
+    filter: ((CONFIG_FLASH_HAS_DRIVER_ENABLED and not CONFIG_TRUSTED_EXECUTION_NONSECURE)
+      and CONFIG_SOC_FAMILY_STM32
+      and dt_label_with_parent_compat_enabled("storage_partition", "fixed-partitions"))
+    integration_platforms:
+      - nucleo_g474re
+    platform_exclude:
+      - nucleo_wb55rg
   drivers.flash.common.non_quad_mode:
     extra_args:
       - EXTRA_DTC_OVERLAY_FILE=boards/mx25r64_non_quad.overlay