util/ide-config.sh: Cleanup
util/ide-config.sh: Cleanup

* Change error messages to print to stderr
* Uglify variables to adhere to shell scripting style

BRANCH=none
BUG=none
TEST=none

Change-Id: I2baef1b9711447b3506c74674db5701e9ba8c753
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2101901
Tested-by: Craig Hesling <383db090fd8ef907a606ac8a9eccd2962bc489cf@chromium.org>
Reviewed-by: Jett Rink <9d4aef0593e6843318d99df31597fb6153b89787@chromium.org>
Commit-Queue: Craig Hesling <383db090fd8ef907a606ac8a9eccd2962bc489cf@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec