util/ectool/Makefile: improve cross-compilation support

Build variables like CC, INSTALL, and PREFIX, should not be
overwritten by the Makefile. This generates problems when we use
different buildsystem like Yocto where tool names are stored in
environment variables. This change may make building util tool
easier - the user of different buildsystem will not have to remember
to pass correct tool names during running the make command.

Also, this change does not affect the rest of users - if the variable
was not set before, then it will be configured as before.

Signed-off-by: Maciej Gabryelski <maciej.gabryelski@3mdeb.com>
Change-Id: If5c88bde0ae00f0211a250906cbdedfe4f59c67b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70102
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Michał Żygowski <michal.zygowski@3mdeb.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions