Fix Flash size (512KB) for STM32F103ZE (#21590)

Marlin/src/HAL/STM32F1/HAL.h

 // ------------------------
 
 #ifndef STM32_FLASH_SIZE
-  #if EITHER(MCU_STM32F103RE, MCU_STM32F103VE)
+  #if ANY(MCU_STM32F103RE, MCU_STM32F103VE, MCU_STM32F103ZE)
     #define STM32_FLASH_SIZE 512
   #else
     #define STM32_FLASH_SIZE 256