bug#38361: GNUmakefile mode: fooled by stuff after single letter variables

[積丹尼 Dan Jacobson]

$ cat makefile
g:
        v.build.polylines input=$Q output=$Q1
$ emacs makefile
Both "$Q"s should look the same.
Just because we put a 1 after the last shouldn't affect it.
The 1 should be a different color than the Q.
If we really wanted to, we would have used $(Q1).
(Here we mean $(Q)1.)
emacs-version "26.3"