Makefile: Fix detection of cross compiler
Makefile: Fix detection of cross compiler

The Fedora containers don't have 'which' installed. This means the
detection of the cross compiler gives false negatives, leaving CROSS
undefined.

Instead use command -v, which outputs the path of the executable if it
exists.

Fixes: 9cd556ca1e5f ("Makefile: Search for distro-provided cross-compiler")
Signed-off-by: Joel Stanley <4816dabf8db1bc6cac35b3a24cab2ff844b5b0c7@jms.id.au>
Signed-off-by: Cédric Le Goater <2d8cace2254d4e43578d21933db015d84bcc468a@kaod.org>

open-power/skiboot,shenki/skiboot,open-power/skiboot,shenki/skiboot,qemu/skiboot,open-power/skiboot,qemu/skiboot,qemu/skiboot,shenki/skiboot,shenki/skiboot,open-power/skiboot,open-power/skiboot,qemu/skiboot,qemu/skiboot,shenki/skiboot