doc: PORTING: drop flash_area_read_is_empty()
Update PORTING guide dropping `flash_area_read_is_empty`.
@@ -119,11 +119,6 @@ int flash_area_erase(const struct flash_area *, uint32_t off, uint32_t len);
uint8_t flash_area_align(const struct flash_area *);
/*< What is value is read from erased flash bytes. */
uint8_t flash_area_erased_val(const struct flash_area *);
-/*< Reads len bytes from off, and checks if the read data is erased. Returns
- 1 if empty (that is containing erased value), 0 if not-empty, and -1 on
- failure. */
-int flash_area_read_is_empty(const struct flash_area *fa, uint32_t off,
- void *dst, uint32_t len);
/*< Given flash area ID, return info about sectors within the area. */
int flash_area_get_sectors(int fa_id, uint32_t *count,
struct flash_sector *sectors);
