Makefile: Allow "gmake target1 target2 -j" (#14312)

Add the .NOTPARALLEL target to each local Makefile command-line
interface entry point file so that even with -j we launch only
one "make -f Makefile2" at a time.  The actual build rules
in Makefile2 and lower will still run in parallel.  Make tools
that do not understand .NOTPARALLEL will not be hurt.

Suggested-by: Robert Luberda <robert-cmake@debian.org>
Merge topic 'make-entry-no-parallel' into next

de15712 Makefile: Allow "gmake target1 target2 -j" (#14312)