it8380dev: util/iteflash
it8380dev: util/iteflash

1. change I2C frequency to 400K.
2. include the support for other it83xx series.
3. add "chip erase" command if the erase size equals to
   flash's physical size.
4. remove 50h command.
5. always check write enable bit of the status reg, after
   write enable command.

Signed-off-by: Dino Li <00c808bcd0610e8dd73a10880490949c0c589d41@ite.com.tw>

BRANCH=none
BUG=none
TEST=servo board + IT83xx EVB can erase, write, and read flash via i2c.
     (iteflash --e, --w, and --r)

Change-Id: I0ac1eeaed5c243215d8817eb45b4b4fe0a7df26a
Reviewed-on: https://chromium-review.googlesource.com/283265
Reviewed-by: Randall Spangler <62698fdbb84d1779579ee80c3f39fac22017e5bc@chromium.org>
Tested-by: Dino Li <00c808bcd0610e8dd73a10880490949c0c589d41@ite.com.tw>
Commit-Queue: Dino Li <00c808bcd0610e8dd73a10880490949c0c589d41@ite.com.tw>

fourier49/BZ_DEV_EC,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,fourier49/BZ_DEV_EC,akappy7/ChromeOS_EC_LED_Diagnostics,fourier49/BZ_DEV_EC,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,akappy7/ChromeOS_EC_LED_Diagnostics,fourier49/BZ_DEV_EC