ci: yocto-check-layer: set BSP machines to be tested

When running yocto-check-layer, we can see the following logs:

INFO: test_machine_signatures (bsp.BSPCheckLayer)
INFO:  ... skipped 'No machines set with --machines.'
INFO: No machines set with --machines.
INFO: test_machine_world (bsp.BSPCheckLayer)
INFO:  ... skipped 'No machines set with --machines.'
INFO: No machines set with --machines.

Because we do not set --machines when running the script, it does not
try to run the tests with each individual machine. When setting
machines, yocto-check-layer will ensure that all signatures do not
change when setting MACHINE for each our supported machine. So we can
catch more errors. Note that this is also what would be done by Yocto
if we wanted to run the compliance tests.

E.g. from Yocto docs:

bsp.test_machine_world: Verifies that bitbake world works regardless
                        of which machine is selected.

bsp.test_machine_signatures: Verifies that building for a particular
                             machine affects only the signature of
                             tasks specific to that machine.

Signed-off-by: Nicolas Dechesne <[email protected]>

ci/yocto-check-layer.sh

@@ -14,5 +14,7 @@ CMD="$CMD --no-auto"
 CMD="$CMD --dependency `pwd`/poky/meta `pwd`/meta-qcom"
 # Disable automatic testing of dependencies
 CMD="$CMD --no-auto-dependency"
+# Set machines to all machines defined in this BSP layer
+CMD="$CMD --machines $(echo $(find $TOPDIR/conf/machine/ -name *.conf -exec basename {} .conf \; ))"
 
 exec kas shell $TOPDIR/ci/base.yml --command "$CMD"