Changed to use accessors instead of casting to volatile pointers.

In places where we were defining memory mapped peripheral buffers we
were using directly a cast to "volatile int_type *". For consistency we
should use dereferenced accessor like: &MMIO32(address)

lib/stm32/f1/flash.c

@@ -122,13 +122,13 @@ void flash_program_word(uint32_t address, uint32_t data)
 	FLASH_CR |= FLASH_CR_PG;
 
 	/* Program the first half of the word. */
-	(*(volatile uint16_t *)address) = (uint16_t)data;
+	MMIO16(address) = (uint16_t)data;
 
 	/* Wait for the write to complete. */
 	flash_wait_for_last_operation();
 
 	/* Program the second half of the word. */
-	(*(volatile uint16_t *)(address + 2)) = data >> 16;
+	MMIO16(address + 2) = data >> 16;
 
 	/* Wait for the write to complete. */
 	flash_wait_for_last_operation();
@@ -143,7 +143,7 @@ void flash_program_half_word(uint32_t address, uint16_t data)
 
 	FLASH_CR |= FLASH_CR_PG;
 
-	(*(volatile uint16_t *)address) = data;
+	MMIO16(address) = data;
 
 	flash_wait_for_last_operation();
 
@@ -196,7 +196,7 @@ void flash_program_option_bytes(uint32_t address, uint16_t data)
 	}
 
 	FLASH_CR |= FLASH_CR_OPTPG;	/* Enable option byte programming. */
-	(*(volatile uint16_t *)address) = data;
+	MMIO16(address) = data;
 	flash_wait_for_last_operation();
 	FLASH_CR &= ~FLASH_CR_OPTPG;	/* Disable option byte programming. */
 }

lib/usb/usb_fx07_common.c

@@ -30,9 +30,8 @@
  * As the code can be used on both cores, the registers offset is modified
  * according to the selected cores base address. */
 #define dev_base_address (usbd_dev->driver->base_address)
-#define REBASE(x)        MMIO32((x)+(dev_base_address))
-#define REBASE_FIFO(x)   ((volatile uint32_t*)((dev_base_address) \
-			                       + (OTG_FIFO(x))))
+#define REBASE(x)        MMIO32((x) + (dev_base_address))
+#define REBASE_FIFO(x)   (&MMIO32((dev_base_address) + (OTG_FIFO(x))))
 
 void stm32fx07_set_address(usbd_device *usbd_dev, uint8_t addr)
 {