Add env variable to specify which toolchain to use

The environment variable TOOLCHAIN can specify whether to use
clang (default), or gcc.

Signed-off-by: Fuad Tabba <tabba@google.com>
Change-Id: I8464f453bfdd5eceea61402981242b1574cf1798
1 file changed
tree: 884693e88f80ddda1357cafc1075583f218b0d1e
  1. Makefile
  2. aarch64/
  3. common.inc
  4. kvm-unit-tests/