devtool: ide_sdk: Use bitbake's python3 for generated scripts

devtool: ide_sdk: Use bitbake's python3 for generated scripts

The generated scripts use the sys.path configuration found inside
bitbake. It can be a different python version than the one used on the
host through the IDE.

For instance, when running the generated script
deploy_target_cmake-example-core2-64 from an eSDK generated on another
machine, I got the following exception:
    AssertionError: SRE module mismatch

We need to match the sys.executable to the sys.path.

Signed-off-by: Enguerrand de Ribaucourt <enguerrand.de-ribaucourt@savoirfairelinux.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>