kinetis cpu flash driver

Initial release of the freescale kinetis cpu flash driver.

src/flash/nor/drivers.c

@@ -45,6 +45,7 @@ extern struct flash_driver stmsmi_flash;
 extern struct flash_driver em357_flash;
 extern struct flash_driver dsp5680xx_flash;
 extern struct flash_driver fm3_flash;
+extern struct flash_driver kinetis_flash;
 
 /**
  * The list of built-in flash drivers.
@@ -75,6 +76,7 @@ static struct flash_driver *flash_drivers[] = {
 	&em357_flash,
 	&fm3_flash,
 	&dsp5680xx_flash,
+	&kinetis_flash,
 	NULL,
 };