lightbar: simplify JUMP, SET_DELAY_TIME opcode execution
lightbar: simplify JUMP, SET_DELAY_TIME opcode execution

We do some unnecessary work here. All we are trying to do is decode,
and decode already does all the error checking we want. Saves
20 bytes.

BUG=None
BRANCH=ToT
TEST=Run programs with JUMP and SET_DELAY_TIME opcodes in simulator
  and on hardware.

Change-Id: Ia55f9010da50fe748bda565e069359162cc92b4f
Signed-off-by: Eric Caruso <b4dfd424537681137c06263971140211e84cb3c6@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/220630
Reviewed-by: Bill Richardson <129945214b1d548d8e49b6c29c43094f8c78057f@chromium.org>

coreboot/chrome-ec,mtk09422/chromiumos-platform-ec,coreboot/chrome-ec,fourier49/BIZ_EC,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,fourier49/BZ_DEV_EC,coreboot/chrome-ec,coreboot/chrome-ec,md5555/ec,fourier49/BIZ_EC,eatbyte/chromium-ec,coreboot/chrome-ec,fourier49/BZ_DEV_EC,longsleep/ec,md5555/ec,longsleep/ec,md5555/ec,akappy7/ChromeOS_EC_LED_Diagnostics,akappy7/ChromeOS_EC_LED_Diagnostics,mtk09422/chromiumos-platform-ec,longsleep/ec,eatbyte/chromium-ec,eatbyte/chromium-ec,md5555/ec,mtk09422/chromiumos-platform-ec,longsleep/ec,fourier49/BZ_DEV_EC,fourier49/BZ_DEV_EC,fourier49/BIZ_EC,eatbyte/chromium-ec,fourier49/BIZ_EC,mtk09422/chromiumos-platform-ec,akappy7/ChromeOS_EC_LED_Diagnostics,akappy7/ChromeOS_EC_LED_Diagnostics