toolchain/60287: Add SPDX-License-Identifier to make sources

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>Number:         60287
>Category:       toolchain
>Synopsis:       Add SPDX-License-Identifier to make sources
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    toolchain-manager
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri May 22 20:05:00 +0000 2026
>Originator:     Simon Gerraty
>Release:        10.0
>Organization:
>Environment:
>Description:
Request from Tuukka Pasanen tuukka.pasanen at ilmi.fi
to add SPDX-License-Identifier to bmake sources.


>How-To-Repeat:

>Fix:
Add suitable SPDX-License-Identifier tags to make sources,
but this might perhaps spark a larger discussion...