Ninja Multi-Config: Fix custom command target dependencies in cross-configs
Generator expressions in a non-cross custom command's COMMAND
arguments are evaluated in the command config. Target-level
dependencies implied by TARGET_FILE
must therefore be cross
dependencies. This is important to generate proper target-level
dependencies on the cross-config build statements for the target to
which the custom command is attached.
Fixes: #22855 (closed)
Backport: release